[0001] The present invention relates to a hydraulic excavator for wells, particularly for
wells of small cross section and of any form and position.
[0002] It is known that in the construction of wells having dimensions greater than a predetermined
value no particular difficulties are encountered with regard to the dimensions of
the type of machine to be used as the latter will go down into the well according
to the degree of advance of the bottom thereof while an external crane or other system
of transport will remove the excavated material. Therefore, the selection of the machine
and its power is within certain limits only determined by the m
3/h to be obtained and the particular geological configuration of the ground.
[0003] However, serious difficulties arise when wells are to be made of dimensions such
that the excavator, which may be of the type supported on pedestals or wheels or caterpillars,
cannot completely penetrate into the well as the latter advances in its construction,
so that the excavation and the depth of the well are limited only by the dimensions
(length) of the excavator arm.
[0004] It is an object of the present invention to eliminate this disadvantage by providing
an excavator for making vertical or inclined wells of any cross section, form and
depth, particularly wells of dimensions and forms that cannot be achieved by the other
types of excavators.
[0005] The excavator according to the invention comprises a supporting column of structural
cross section; a hydraulic pump and associated control box for feeding the hydraulic
system; a motor driving said pump; a hydraulically operated articulated arm having
one end mounted on a pivot secured to the column to permit rotation of the arm through
1B
Oo about its axis extending parallel to the longitudinal axis of the column; a detachable
working tool connected to the opposite end of said arm, said working tool being likewise
hydraulically operated, and a control system for guiding the articulated arm and the
working tool, said column serving as a supporting frame receiving the other parts
of the excavator and for anchoring and the descent of the excavator along the wall
of the well, said articulated arm being driven by a pair of hydraulic rams for rotation
about the axis cf said pivot and being pivotally connected by hinges to said pivot
to permit the articulated arm also to be lifted.
[0006] The accompanying drawings show a preferred, not limiting embodiment of the excavator
in question.
[0007]
Fig. 1 is a side view of an excavator according to the invention;
Fig. 2 is a top plan view of the excavator in its position on a well to be prepared,
and
Fig. 3 is a side view of the excavator in its operative position within the well.
[0008] New hereafter a description will be given of a particular embodiment of the invention
with reference to the Figures of the accompanying drawings without, for the rest,
taking away anything from the generality of the invention.
[0009] The excavator comprises a supporting column 1 having a structural shape for supporting
the other parts of the excavator and serving for coupling the excavator to anchoring
means provided on the inner jacket 20 of the well 21, the jacket 20 being made of
concrete. The supporting column 1 is appropriately shaped to permit it to be anchored
by means of brackets 7 and bolts 8 to the inner jacket 20 of the well 21. Alternatively
the supporting column 1 may have a groove la of appropriately shaped cross section
to permit it to be guided on a rail secured to the inner jacket of the well 21, so
that with the further addition of a hydraulic control unit the excavator will behave
in the manner of a lift whose upward and downward movements can be controlled by the
operator.
[0010] The brackets 7 may be crescent-shaped to ensure a more uniform distribution of the
strain and prevent the concrete from crumbling. The supporting column 1 has an L-shaped
head portion lb provided with a hook lc at the end facing the excavator arm, this
hook being located in the vicinity of the centre of gravity so that the excavator
arm can be conveniently suspended thereon to facilitate lifting, transport and introduction
of the excavator in the well to be prepared and removal of the excavator when the
well is finished.
[0011] The lower end portion of the supporting column is provided with a projecting shelf
ld carrying an operator's seat 9, control means 6 and a control panel 10 as well as
a pivot 11 to which an articulated arm 4 is secured. The pivot 11 can be moved by
a pair of hydraulic rams 12 secured to opposite sides thereof so that the articulated
arm can be rotated through 180
0 about the longitudinal axis of the supporting column 1.
[0012] The arm 4 is composed of two portions 4a and 4b which are pivotally connected to
each other. The lifting movement of the portion 4a in the vertical plane of the column
is controlled by a hydraulic ram 4c and the rotary movement of the portion 4b relative
to the portion 4a is controlled by a hydraulic ram 4d.
[0013] The length of the arm is variable and also a telescoping arm may be mounted.
[0014] The desired working tool 5 best suited for the excavation to be effected is mounted
at the distal end of the portion 4b of the articulated arm 4. It may be a shovel which
could also be hydraulically operated by means of the piston 5a, or an inverted bucket
or a demolishing hammer or a drill column according to the required type of work.
[0015] The hydraulic pump 2 is mounted on one side of the projecting shelf for feeding hydraulic
fluid through a hydraulic control box 13 to the hydraulic devices of the system (pistons
and rams). The hydraulic fluid tank 14 is mounted on the upper.portion of the column.
[0016] Such pump is driven by a motor 3 which may be an electric motor or an internal combustion
engine. The motor 3 may be mounted directly on the excavator (beside the pump) or
may be located outside the well.
[0017] The solution comprising an internal combustion engine located outside the well affords
the advantage that the excavator can be used where no connection to electric mains
is possible and by positioning the engine outside the well the air inside the well
is not contaminated, thus avoiding harmful effects to the operator. Thus, this solution
is particularly suitable for use in remote places where no connection to electric
mains is possible.
[0018] Step irons 15 on the supporting column 1 facilitate access to the operator's seat.
In a typical embodiment the excavator has a height of 4 metres, a width of 1,30 metres
and a length of 1,10 metres without the articulated arm and the working tool. Thus,
the overall cross-sectional dimensions of the excavator are very small, permitting
it to be used for making wells of small diameter which cannot be made by conventional
excavators.
[0019] In making wells whose cross-sectional dimensions do not exceed a certain value there
will be a moment corresponding to a certain depth of the well, at which the conventional
excavators of the type mounted on a gantry, wheels or caterpillars, cannot go.any
further down into the well and by using too long excavator arms the static stability
of the excavator is jeopardized.
[0020] The present invention permits to overcome these problems by operating in the following
manner:
After the upper portion of the well has been initially prepared, it is lined with
a concrete jacket 20 to which anchoring means or a rail is secured. The present excavator
(Fig. 3) is then secured to this anchoring means or rail to work on the bottom of
the well and increase its depth as far as permitted by the length of the excavator
arm. Then the well is lined with a new concrete jacket which may be prefabricated
or formed of standard parts and further anchoring means are secured to this new jacket
or alternatively the rail is extended by adding a new length of rail thereto. Then
the excavator is again ready to continue its excavation work.
[0021] Also a plurality of anchoring means or rails may be secured to the inner surface
of the jacket 20 of the well 21 to increase the maneuvrability of the excavator within
the well. In this manner, for example, the excavator may be rotated through 180° about
the longitudinal axis of the column to cover the entire range of rotation of 360 .
[0022] For making inclined wells the operator may remain on the ground and control the excavator
by means of an electric control panel. Also in this manner wells of any cross section,
dimension and shape may be made of any desired depth and both vertically and in an
inclined direction.
[0023] Thus, the present invention provides a handy excavator of reduced size and high efficiency
and low operating costs. This excavator is made of standard materials and suitable
for making vertical or inclined wells of any desired cross section and shape, particularly
for making wells of small diameter or of oblong shape. It is particularly adapted
for use in remote areas that are not easily accessible and it can excavate a well
depth of 1-2 metres per day.
1. Hydraulic excavator for wells, comprising a supporting column (1) of structural
cross section; a hydraulic pump (2) and associated control box (13) for feeding the
hydraulic system; a motor (3) driving said pump (2);, a hydraulically operated articulated
arm (4) having one end mounted on a pivot (11) secured to the column (1) to permit
rotation of the arm through 1800about its axis extending parallel to the longitudinal
axis of the column (1); a detachable working tool (5) connected to the opposite end
of said arm (4), said working tool being likewise hydraulically operated, and a control
system (6) for guiding the arm (4) and the tool (5), said column (1) serving.as a
supporting frame receiving the other parts of-the excavator and for anchoring and
the descent of the excavator along the wall of the well, said arm (4) being driven
by a pair of hydraulic rams (12) for rotation about the axis of said pivot (11) and
being pivotally connected by the hinges (16) to said pivot to permit the arm also
to be lifted..
2. Excavator according to claim 1, characterized in that a dovetailed groove (la)
extends longitudinally through the portion of the column (1) facing the wall of the
well to permit the column to be secured to a rail fixed on the jacket of the well
so that the excavator can be moved hydraulically in the manner of a lift.
3. Excavator according to claim 1 or 2, characterized in that the column has an L-shaped
head portion (lb) provided with a hook (lc) at the end facing the arm (4) to permit
- the excavator to be suspended in a balanced position.
4. Excavator according to claim 1, characterized in that said articulated arm (4)
is of the telescoping type of variable length.
5. Excavator according to claim 1, characterized in that the motor (3) is an electric
motor.
6. Excavator according to claim 1, characterized in that the motor (3) is an internal
combustion engine.
7. Excavator according to claim 5 or 6, characterized in that the motor is mounted
directly on the excavator or located outside the well.
8. Excavator according to any of the preceding claims, characterized in that the working
tool is a bucket of a shape and size adapted for the type of excavating work.
9. Excavator according to claim 8, characterized in that the bucket is mounted in
inverted position.
10. Excavator according to one of claims 1 to 7, characterized in that the working
tool is a demolishing hammer.
11. Excavator according to one of claims 1 to 7, characterized in that the working
tool is a drill column.
12. Use of the excavator according to claim 1 for making vertical or inclined wells
of any cross section and shape, particularly of small cross section.