Field of the invention
[0001] The invention relates to a snow plough, and particularly to a blade bench of a snow
plough.
Field of the invention
[0002] Snow ploughs to be attached, among other things, to lorries or trucks, tractors or
other work machines are used for removing snow from roads, streets, parking spaces,
airport runways and the like. A snow plough comprises a wing and, in a lower part
of the wing, a blade bench to which are fastened blades, also called wear blades,
for carrying out detachment of snow and ice from a surface being ploughed.
Brief description of the invention
[0003] An object of the invention is to provide a novel blade bench of a snow plough, and
a snow plough.
[0004] The solution according to the invention is characterized by what is disclosed in
the independent claims.
[0005] Some embodiments of the invention are disclosed in the dependent claims.
[0006] According to an embodiment, the blade bench of the snow plough comprises a frame
of the blade bench and a plurality of mutually separate blade holders in a horizontal
direction of the blade bench, mutually separate wear blades of the snow plough being
arrangeable in connection with the blade holders, and wherein the blade holders are
spring-loaded, allowing the blade holders and the wear blades to move mutually separately
in a vertical direction of the blade bench and to incline mutually separately with
respect to the horizontal direction of the blade bench, and wherein in an operating
position of the snow plough, the blade holders and the wear blades are in an upward
sprung position.
[0007] When the blade bench comprises in the horizontal direction a plurality of mutually
separate blade holders and wear blades which are allowed to move in the vertical direction
mutually separately, i.e. irrespectively of the other blade holders and the wear blades
associated therewith, the blades of the snow plough are capable of following closely
the surface to be ploughed and possible rough spots therein, thus enabling the snow
collected on the surface to be ploughed to be removed efficiently, regardless of any
roughness therein.
[0008] When the blade holders and the wear blades provided in connection therewith are in
the operating position of the snow plough in the upward sprung position, a spring
force presses the blade holders and the wear blades provided in connection therewith
downwards, against the surface to be ploughed. When a wear blade comes to reside at
a groove or some such rough spot in the surface to be ploughed, the wear blade moves
down to the bottom of the groove or some such rough spot, thus following the surface
to be ploughed due to the influence of the spring force pressing the wear blade downwards.
In such a case, the groove or some such rough spot may be cleaned of snow all the
way down to its bottom, without any snow remaining therein to become transformed into
ice later. Consequently, the ploughing quality and result remain good on a surface
comprising grooves or some such rough spots.
[0009] Similarly, when the snow plough meets a protrusion in the surface to be ploughed,
one or more wear blades residing at the protrusion are allowed to move up, irrespectively
of the other wear blades, while wear blades that do not meet the particular protrusion
remain pressed against the surface to be ploughed. If the play of the wear blade upwards
is insufficient, the entire plough moves up and wear blades remaining outside the
protrusion are pressed downwards due to the influence of the spring force. Consequently,
the ploughing quality and result remain good and excellent also on a surface comprising
protrusions.
[0010] Further, when the blade holder and the wear blade associated therewith are allowed
to incline with respect to the horizontal direction of the blade bench, irrespectively
of the other blade holders and the wear blades associated therewith, the wear blades
are also allowed to follow possible inclinations in the surface to be ploughed, in
which case the ploughing quality and result remain good and excellent also on a surface
comprising inclinations.
[0011] According to an embodiment of the blade bench, the blade bench comprises slot elements
arranged in connection with the frame of the blade bench and provided with a slot,
and the blade holders comprise brackets arranged in the slots, said slots forming
a structure controlling the movement and inclination of the blade holders.
[0012] According to an embodiment of the blade bench, a flexible element used for producing
spring load is a leaf spring directed in the horizontal direction of the blade bench,
and the blade holder is arranged in connection with the leaf spring by means of at
least two support elements arranged to be pressed in the vertical direction of the
blade bench against the leaf spring at substantially opposite ends of the leaf spring.
[0013] According to an embodiment of the blade bench, the leaf spring is supported on the
frame of the blade bench in the horizontal direction of the blade bench by means of
a fastener located substantially centrally on the leaf spring, the fastener forming
a fixed pivot point to allow the blade holder and the wear blade provided in connection
therewith to incline with respect to the horizontal direction of the blade bench.
[0014] According to an embodiment of the blade bench, the blade holders are arranged on
a front side of the frame of the blade bench while the flexible elements producing
spring load are arranged on a rear side of the frame of the blade bench.
[0015] According to an embodiment of the blade bench, the blade bench comprises a wear element
arranged between the frame of the blade bench and the blade holder in order to reduce
wear of the frame of the blade bench when the blade holder moves with respect to the
frame of the blade bench.
[0016] According to an embodiment, the snow plough comprises a wing and a blade bench, wherein
the blade bench is a blade bench as claimed in any one of claims 1 to 6.
[0017] According to an embodiment of the snow plough, the blade bench is fastened to the
wing detachably.
[0018] According to an embodiment of the snow plough, the snow plough is a side plough.
Brief description of the figures
[0019] The invention is now described in closer detail in connection with preferred embodiments
and with reference to the accompanying drawings, in which:
Figure 1 schematically shows a snow plough as viewed from behind,
Figure 2 schematically shows a front diagonal view of a blade bench of a snow plough
according to Figure 1,
Figure 3 schematically shows a rear diagonal view of the blade bench of a snow plough
according to Figure 1,
Figure 4 schematically shows a front diagonal view of a detail of the blade bench
of a snow plough according to Figure 1, and
Figure 5 schematically shows a partially exploded front diagonal view of the blade
bench of a snow plough according to Figure 1.
[0020] For the sake of clarity, the figures show some embodiments of the invention in a
simplified manner. In the figures, like reference numerals identify like elements.
Detailed description of the invention
[0021] Figure 1 schematically shows a snow plough 1 as viewed from behind. The snow plough
1 may be attached, for instance, to lorries or trucks, tractors or another work machine
in order to remove snow from roads, streets, parking spaces, airport runways or the
like. The snow plough 1 comprises a wing 2 and a blade bench 3 fastened to a lower
part of the wing 2.
[0022] Figure 2 schematically shows a front diagonal view of the blade bench 3 according
to Figure 1, Figure 3 schematically shows a rear diagonal view of the blade bench
3 according to Figure 1, Figure 4 schematically shows a front diagonal view of a detail
of the blade bench 3 according to Figure 1, and Figure 5 schematically shows a partially
exploded front diagonal view of the blade bench 3 according to Figure 1.
[0023] Referring to Figures 2 to 5, the blade bench 3 comprises a frame 4 having a front
side 4' to be facing forwards, and a rear side 4" to be facing backwards. The blade
bench 3 further comprises in a horizontal direction H of the blade bench 3 a plurality
of successive, mutually separate blade holders 5 arranged on the side of the front
side 4' of the frame 4 of the blade bench 3 such that they are allowed to move mutually
separately in a vertical direction V of the blade bench 3. Blades 6, i.e. wear blades
6, for carrying out detachment of snow and ice from the surface to be ploughed are
fastened in connection with the blade holders 5, in which case the blade bench 3 comprises
in the horizontal direction H a plurality of successive, mutually separate wear blades
6 which are allowed to move mutually separately in the vertical direction V of the
blade bench 3. Herein, the vertical direction of the blade bench refers to a direction
oriented upwards from the surface to be ploughed which converges with the direction
of the wear blade 6 when viewing the wear blade in the vertical direction of the snow
plough. Typically, the wear blades 6 are arranged slightly aslant with respect to
the absolute vertical direction. The direction of the wear blade 6 may be determined
by a blade angle, which indicates an angle between the wear blade and the surface
to be ploughed. The vertical movement of the blade holders 5 and the wear blades 6
to be fastened in connection therewith is implemented in a spring-loaded manner. Spring
loading is produced by flexible elements which enable both the mutually separate vertical
movement of the blade bench 3 and the mutually separate inclination with respect to
the horizontal direction of the blade bench 3 of the in the horizontal direction H
of the blade bench 3 successive, mutually separate blade holders 5 and the wear blades
6 to be fastened in connection therewith.
[0024] In the solution according to Figures 2 to 5, the flexible elements are leaf springs
8 fastened to the rear side 4" of the frame 4 of the blade bench 3 such that the leaf
spring 8 is directed in the horizontal direction of the blade bench 3 or runs in the
horizontal direction of the blade bench 3. The leaf spring 8 is fastened by a fastener
9 to the frame 4 of the blade bench 3 substantially at its centre in the horizontal
direction of the blade bench 3 such that ends 8a and 8b of the leaf spring 8 remain
free with respect to the frame 4 of the blade bench 3. The number of leaf springs
8 provided in the horizontal direction of the blade bench 3 equals the number of blade
holders 5, i.e. the blade bench 3 is provided with a leaf spring 8 associated with
each blade holder 5.
[0025] The blade holder 5 is arranged in the blade bench 3 by means of slot elements 10
which, in the solution according to Figures 2 to 5, are fastened to the front side
4' of the frame 4 of the blade bench 3 such that a slot 11 of the slot element 10
is directed towards the front side 4' of the frame 4 of the blade bench 3. The slot
elements 10 are placed in the blade bench 3 in the horizontal direction thereof such
that a slot element 10 comes to reside at each end 5a, 5b of the blade holders 5,
in which case when assembling the blade bench 3, a bracket 12 provided at each end
5a, 5b of the blade holders 5 and directed outwards from the end of the blade holders
settles in the slot 11. In such a case, the slot elements 10 support the blade holder
5 on the blade bench 3 while at the same time the slots 11 form vertical grooves in
which the brackets 12 provided at the ends 5a, 5b of the blade holders 5 are allowed
to move in the vertical direction of the blade bench 3 within the extreme limits determined
by ends 11 a, 11b of the slot 11, thereby enabling the blade holder 5 and the wear
blade 6 to move in the vertical direction of the blade bench 3 within the extreme
limits determined by the ends of the slot. The slot elements 10 may be fastened to
the frame 4 of the blade bench 3 by screws 13 and washers 14, for instance.
[0026] The blade holder 5 is arranged in connection with the leaf spring 8 by means of support
elements 15. To be more precise, the arrangement according to Figures 2 to 5 includes
widened bores 16 formed in a lower part of the frame 4 of the blade bench 3, below
the ends 8a, 8b of the leaf spring 8, through which the support elements 15 are arranged
to pass in a direction between the front side 4' and the rear side 4" of the frame
4 of the blade bench 3. The support element 15 is arranged in connection with the
blade holder 5 for instance such that a fastening screw 17 is arranged to run from
a direction of the front side 4' of the frame 4 of the blade bench 3 in a direction
of the rear side 4" of the frame 4 of the blade bench 3, through the wear blade 6
and the blade holder 5 and extending all the way to the support element 15 such that
the fastening screw 17 connects the wear blade 6, the blade holder 5 and the support
element 15 to one another, into one structure. The fastening screw 17 and a nut 19
fasten the wear blade 6 to the blade holder 5. In a direction of the fastening screw
17, the support element 15 provides a support surface for the leaf spring 8. The support
element 15 is wound in to the fastening screw 17, in which case the support element
15 provides the ends 8a, 8b of the leaf spring 8 with a support surface which supports
the end 8a, 8b of the leaf spring from below the leaf spring 8.
[0027] The blade bench 3 is fastened for instance by screw fastening or some other fastening
manner detachably to the wing 2 of the snow plough 1. Alternatively, the blade bench
3 may be a fixed part of the plough 1. When using the snow plough 1, the blade holders
5 are allowed to move mutually separately in the vertical direction of the blade bench
3 within the limits determined by the slots 11 of the slot elements 10, the lower
end 11 a of the slot 11 of the slot element 10 determining the maximum limit of movement
of the blade holder 5 with respect to the frame 4 of the blade bench 3 downwards.
The upper end 11 b of the slot 11 of the slot element 10, in turn, determines the
maximum limit of movement of the blade holder 5 upwards. The widened bore 16 is, in
turn, dimensioned such that a total length of travel determined by the lower and upper
ends 11 a, 11 b of the slots 11 of the slot elements 10 is available.
[0028] The fastener 9 of the leaf spring 8 forms a fixed pivot point between the ends 8a,
8b of the leaf spring 8, as a consequence of which the support elements 15 located
at the opposite ends 8a, 8b of the leaf spring 8 are allowed to move in the vertical
direction of the blade bench 3, irrespectively of one another. Taking also into consideration
that since the blade holders 5 are arranged by means of the slot elements 10 in the
blade bench 3, which results in clearances between adjacent blade holders 5, this
means that the blade holder 5 and the wear blade 6 associated therewith are allowed
to incline with respect to the horizontal direction of the blade bench 3, irrespectively
of the other blade holders and the wear blades associated therewith, and thus to follow
inclinations possibly provided in the surface to be ploughed.
[0029] The blade holders 5 are arranged by means of the support elements 15 to be in connection
with the corresponding leaf springs 8 such that the blade holders 5 and the wear blades
6 in connection therewith are in the operating position of the snow plough 1 in an
upward sprung position, i.e. in the operating position of the snow plough 1 the leaf
springs 8 are in a strained state and press the blade holders 5 downwards. In such
a case, when a wear blade 6 comes to reside at a groove or some such rough spot in
the surface to be ploughed, the wear blade 6 moves down to the bottom of the groove
or some such rough spot due to the influence of the spring force pressing it downwards.
[0030] Further, when the snow plough 1 meets a protrusion in the surface to be ploughed,
one or more wear blades 6 residing at the protrusion are allowed to move up, irrespectively
of the other wear blades 6, against the spring load produced by the leaf spring 8
and within the limits of the slot 11. The wear blades 6 that do not meet said protrusion,
in turn, remain pressed against the surface to be ploughed. Consequently, the ploughing
quality and result remain good and excellent.
[0031] The leaf spring 8, the slot 11 and the widened bore 16 may be dimensioned or adapted
in relation to one another such that in the operating position of the snow plough
1 the springing allowance of the wear blades 6 is smaller upwards than it is downwards.
This means that in the operating position of the snow plough 1, a significant force
resulting from the strained state of the leaf springs 8 and pressing the wear blades
6 downwards is applied to the wear blades to enable the wear blades 6 to descend to
the bottom of the groove or some such rough spot in the surface to be ploughed. According
to an embodiment, the leaf spring 8, the slot 11 and the widened bore 16 may be dimensioned
or adapted in relation to one another such that in the operating position of the snow
plough 1 the springing allowance of the wear blade 6 upwards is for instance about
5 mm and downwards for instance about 25 mm, a total springing allowance thus being
about 30 mm.
[0032] The above-disclosed solution may be used both in front ploughs and in side ploughs.
The disclosed solution is particularly advantageous in ploughs typically employing
a very slight blade angle, for instance of less than 60 degrees, when a blade angle
is defined as an angle between a backing surface of the wear blade, i.e. the backwards
facing surface of the wear blade, and the surface to be ploughed.
[0033] The wear blades 6 may be for instance hard metal blades, and their width may vary
depending for instance on the use, i.e. for instance on the snow plough to which they
are applied, i.e. for instance on whether the plough is a front plough or a side plough.
With respect to the total length of the blade bench 3, single wear blades may be made
quite short, which makes a worn or damaged single wear blade 6 relatively quick and
easy to replace by a new one.
[0034] Further, Figure 5 shows a wear element 7, such as for instance a stainless steel
plate, which may be placed between the blade holder 5 and the frame 4 of the blade
bench 3; to be more precise, between the slot elements 10 and the front side 4' of
the frame 4 of the blade bench 3. The wear element 7 reduces friction and prevents
wear when the blade holder 5 moves with respect to the surface of the front side 4'
of the frame 4 of the blade bench 3.
[0035] Figure 5 further shows a corner piece 22 which is fastened fixedly for instance by
screws 20 and nuts 21 to an end of the blade bench 3 to protect the tip of the snow
plough 1 and whose outwardly facing edge comprises a bevel 23 at a lower part thereof.
[0036] According to an embodiment, as distinct from the embodiment disclosed in the figures,
the leaf spring 8 may be supported on the frame 4 of the blade bench 3 also by means
of a fastener 9 located at one end of the leaf spring 8, and the support elements
15 pressing against the leaf spring 8 may be located centrally on the leaf spring
8 as well as at its opposite end, in which case the centrally located support element
15 forms a pivot point for the leaf spring. A one-piece leaf spring may also be divided
into two leaf spring sections that are supported on the frame 4 of the blade bench
3 in its horizontal direction substantially at the same point, in which case said
leaf spring sections may be considered to have at least one common fulcrum.
[0037] According to an embodiment, the leaf springs 8 shown in Figure 3 may be completed
by using coil or cup springs as auxiliary springs by means of fastening members implemented
therefor. The leaf springs 8 may also be replaced by using in their place only coil
or cup springs by means of fastening members implemented therefor.
[0038] It will be apparent to a person skilled in the art that as technology advances, the
basic idea of the invention may be implemented in many different ways. The invention
and its embodiments are thus not restricted to the examples described above but may
vary within the scope of the claims.
1. A blade bench (3) of a snow plough (1), comprising
a frame (4) of the blade bench (3) and
a plurality of mutually separate blade holders (5) in a horizontal direction (H) of
the blade bench (3), mutually separate wear blades (6) of the snow plough (1) being
arrangeable in connection with the blade holders (5), and at least one flexible element
associated with each blade holder (5), the blade holder (5) being arranged in connection
with the flexible element such that the blade holders (5) and the wear blades (6)
provided in connection therewith are allowed to move mutually separately in a vertical
(V) direction of the blade bench (3) and to incline mutually separately with respect
to the horizontal (H) direction of the blade bench (3), and wherein in an operating
position of the snow plough (1), the blade holders (5) and the wear blades (6) are
in an upward sprung position, characterized in that the flexible element is a leaf spring (8) directed in the horizontal (H) direction
of the blade bench (3), and in that the blade holder (5) is arranged in connection with the leaf spring (8) by means
of at least two support elements (15).
2. A blade bench (3) as claimed in claim 1, characterized in that the blade bench (3) comprises slot elements (10) arranged in connection with the
frame (4) of the blade bench (3) and provided with a slot (11), and wherein the blade
holders (5) comprise brackets (12) arranged in the slots (11), said slots (11) forming
a structure controlling the movement and inclination of the blade holders (5).
3. A blade bench (3) as claimed in claim 1 or 2, characterized in that the support elements (15) are arranged to be pressed in the vertical (V) direction
of the blade bench (3) against the leaf spring (8) at substantially opposite ends
(8a, 8b) of the leaf spring (8).
4. A blade bench (3) as claimed in claim 3, characterized in that the leaf spring (8) is supported on the frame (4) of the blade bench (3) in the horizontal
(H) direction of the blade bench (3) by means of a fastener (9) located substantially
centrally on the leaf spring (8), the fastener (9) forming a fixed pivot point to
allow the blade holder (5) and the wear blade (6) provided in connection therewith
to incline with respect to the horizontal (H) direction of the blade bench (3).
5. A blade bench (3) as claimed in any one of the preceding claims, characterized in that the blade holders (5) are arranged on a front side (4') of the frame (4) of the blade
bench (3) while the flexible elements producing spring load are arranged on a rear
side (4") of the frame (4) of the blade bench (3).
6. A blade bench as claimed in claim 5, characterized in that the blade bench (3) comprises a wear element (7) arranged between the frame (4) of
the blade bench (3) and the blade holder (5) in order to reduce wear of the frame
(4) of the blade bench (3) when the blade holder (5) moves with respect to the frame
(4) of the blade bench (3).
7. A snow plough (1) comprising a wing (2) and a blade bench (3), characterized in that the blade bench (3) is a blade bench (3) as claimed in any one of claims 1 to 6.
8. A snow plough as claimed in claim 7, characterized in that the blade bench (3) is fastened to the wing (2) detachably.
9. A snow plough (1) as claimed in claim 7 or 8, characterized in that the snow plough (1) is a side plough.