[0001] The present invention relates to excavators - self-moving machines with wheels, tracks
or articulated supports, provided with an upper structure or turret, normally apt
to rotate by 360° and supporting an excavating boom, and mainly designed to excavate
with a shovel or a bucket, while remaining stationary - and concerns, more particularly,
a revolving blade for compact or small excavators (excavators with an operative mass
below 6,000 Kg).
[0002] It is known that, at present, almost all the small excavators are provided with a
front stabilizing blade (known as "scraper") of the fixed type, with the blade profile
perpendicular to the forward moving direction. The functions carried out by the scraper
are essentially two: the first (and most important) is to provide for a stabilizing
action for the small excavator during excavation or load lifting (so as to avoid the
problems deriving from its reduced size and reduced weight), the second function is
its use in refilling and resetting actions by operating a double-acting cylinder.
[0003] When performing refilling operations, the high limit of conventional scrapers in
small excavators is to have a fixed profile; thus, when having to close an excavation,
the operator is forced to perform various maneuvers with the bottom car of the machine
to successfully complete the operation, or else - when the excavation sites are close
to roads - he is forced to close the excavation with the bucket, unless wishing to
occupy the entire lane with the machine.
[0004] The object of the present invention is to overcome or at least reduce such drawbacks
in small excavators, while maintaining the characteristics of slenderness, maneuverability
and simplicity typical of these machines, without making the construction more difficult
and/or increasing the costs in a significant way.
[0005] This purpose is achieved by equipping small excavators with a revolving blade of
simple structure and easy to maneuver, which forms the object of the present invention.
[0006] The revolving blade according to the present invention comprises a support frame
and a blade unit, and is characterized in that the support frame consists of two side
members and at least one cross member; in that the blade unit with the actual blade
comprises a U-shaped support, on each of the arms of which a plurality of holes are
formed, distributed along a circle arc, two similar holes being formed at the outer
ends of the side members of the support frame; and in that the blade unit is apt to
be connected to the support frame in a plurality of differently oriented positions,
by inserting a couple of pins in said two holes of the frame side members and in holes
of said U-shaped support, brought in alignment with the first ones.
[0007] Preferably, said holes in the side members of the support frame are formed in correspondence
of said cross member.
[0008] To said blade there are advantageously associated two extensions, to be mounted in
correspondence of the blade in a working position, and behind the actual blade in
a rest position.
[0009] A preferred embodiment of the revolving blade for small excavators according to the
present invention will now be described in further detail, by way of example, with
reference to the accompanying drawings, in which:
[0010] Figs. 1 and 2 are a side view and a top view of a small excavator equipped with a
conventional fixed blade or scraper;
[0011] Fig. 3 is a general perspective view of the revolving blade according to the present
invention;
[0012] Figs. 4 and 5 are, respectively, a top view and a side view, on a larger scale, of
the revolving blade shown in fig. 3;
[0013] Figs. 6 and 7 are two perspective views, a front view and respectively a rear view,
with disassembled parts, of the revolving blade according to the invention shown in
Figs. 3 to 5;
[0014] Figs. 8 and 9 are a side view and a top view of a small excavator equipped with the
revolving blade of Figs. 3 to 7, oriented with an inclination towards the right side
of the machine; and
[0015] Fig. 10 is a top view, similar to that of Fig. 8, of a small excavator equipped with
the revolving blade of Figs. 3 to 7, in which the blade is shown not inclined and
with the extensions mounted on the inside.
[0016] As can be seen from Figs. 1 and 2, the small excavators of prior art, provided with
a turret T rotatably mounted on a bottom car S with tracks C, are equipped - as well
as with an excavating boom BE ending with a bucket B, carried by the turret T - with
a fixed blade or scraper R carried on the front of the bottom car S.
[0017] According to the invention, it is now provided to equip small excavators of the type
shown in Figs. 1 and 2, with a revolving blade as shown in Figs. 3 to 7, to provide
several advantages.
[0018] As shown in Figs. 3 to 7, the revolving blade L according to the invention comprises
a support frame 1, with two side members 2 and at least one cross member 3, and a
blade unit 4, with an actual blade 5 and a U-shaped support 6 for said blade.
[0019] The support frame 1 comprises, at the free ends of the side members 2, ears 2A for
hingeing onto the bottom car S of the small excavator and usually includes a second
cross member 3A for connection to a cylinder-piston unit of the small excavator, which
controls the vertical movement of the frame itself and thus of the revolving blade
L.
[0020] The four arms 7 of the U-shaped support 6 each have three holes 8, formed along circle
arcs whose center (Fig. 4) corresponds to the outermost hole 8 closer to the blade
5 of the opposite boom 7, while two holes 9 (Figs. 5 and 6) are provided at the outer
ends of the side members 2 of the frame 1, where they connect to the cross member
3. Stout pins 10, equipped with comfortable gripping and operating handles 11, allow
to connect the blade 5 to the frame 1 in different positions (see Fig. 4), after having
aligned each hole 9 of the side members 2 with a pair - selected according to the
orientation one wishes to give to the revolving blade L - of holes 8 of the arms 7
of the support 6, by inserting therein the pins 10. These pins 10 have the double
function of fulcrum for the rotation to orient and block the support 6 in an angular
position, or in a normal position.
[0021] The revolving blade L according to the invention is completed by providing two extensions
12, apt to be mounted on both sides of said blade (or both on the same side, one next
to the other), to allow the track of the small excavator, when the blade L is mounted,
to keep away from the trench (and thus in safe working conditions) during the reclosing
step. The two extensions 12, when not used, can be housed within the side-play of
the central blade, as shown in Figure 10.
[0022] The revolving blade L according to the present invention can be very easily oriented
both towards the right and towards the left. To orient the blade towards the right
(see Figs. 8 and 9) it is sufficient - starting from the normal, straight position
of Fig. 4 - to remove the left pin 10, to rotate the blade in respect of the right
pin 10 (left in its place) and to reset the left pin 10 in the wanted position. To
orient the blade towards the left (not shown) one proceeds as above, but inverting
the pins.
[0023] The particular configuration of the revolving blade according to the present invention
and its operating principle (with only two pins having the double function of orienting
fulcrum and of locking fulcrum) allow to maintain the same forward projection of the
blade profile, without having to use a particularly large blade which would thus limit
the excavating potential.
[0024] The stabilizing function of the revolving blade according to the present invention
remains unvaried in respect of the function of a conventional fixed blade since, with
the blade in a lowered position, the rotation of the front blade unit occurs around
pins perpendicular to the ground, allowing the lower profile of the blade to remain
parallel to the soil, by resting on its entire length and thus ensuring steadiness.
[0025] Besides, the revolving blade according to the present invention introduces, in respect
of prior art, the considerable advantage of allowing small excavators to refill trenches,
or to level soils and roadbeds, or to remove snow or debris from streets and squares,
through the normal rectilinear translation of the excavator (i.e. without being forced
to perform continuous back and forth maneuvers, as it happened up-to-date with these
machines, making use of a conventional fixed blade).
[0026] It is understood that other embodiments of the revolving blade for small excavators,
differing from that described heretofore by way of example, can be conceived without
departing from the scope of the present invention.
[0027] The invention also comprises small excavators equipped with a revolving blade as
described and illustrated hereabove.
[0028] It is finally evident that the revolving blade according to the present invention,
although it was conceived to equip small excavators and is actually apt to provide
its best performances in association therewith - as just seen - can always be associated,
with similar advantages even if less considerable, also to excavators which are heavier
and larger than the compact ones.
1. Revolving blade for compact excavators (or miniexcavators), of the type comprising
a support frame (1) and a blade unit (4), characterized in that the support frame (1) consists of two side members (2) and at least one cross member
(3); in that the blade unit (4) with the actual blade (5) comprises a U-shaped support (6), on
each of the arms (7) of which a plurality of holes (8) are formed, distributed along
a circle arc, two similar holes (9) being formed at the outer ends of the side members
(2) of the support frame (1); and in that the blade unit (4) is apt to be connected to the support frame (1) in a plurality
of differently oriented positions by inserting a couple of pins (10) in said two holes
(9) of the side members (2) of the frame (1) and in holes (8) of said U-shaped support
(6) brought in alignment with the first ones.
2. Revolving blade as in Claim 1), wherein said holes (9) in the side members (2) of
the support frame (1) are formed in correspondence of said cross member (3);
3. Revolving blade as in Claims 1) and 2), wherein said plurality of holes (8) formed
on the arms (7) of the support frame (1) comprises three holes;
4. Revolving blade as in Claims 1) to 3), wherein two extensions (12) are associated
thereto;
5. Revolving blade as in Claim 4), wherein said extensions (12) can be associated to
one and/or the other end of the blade (5) in a working position, and behind the actual
blade (5) in a rest position.