Background of the invention
[0001] The invention relates to scrapers and, in particular, to a scraper blade.
[0002] Scrapers may be used for example for cleaning different surfaces or areas. A scraper
typically comprises a scraper shaft or a shaft portion and a scraper blade fastened
thereto.
Brief description of the invention
[0004] An object of the invention is to provide a novel scraper blade and a scraper.
[0005] The scraper blade of the invention is characterized by the features of the independent
claim.
[0006] The scraper and the scraper blade of the invention may be used e.g. as a snow tool,
for example for removing relatively thin layers of snow from passages, such as pedestrian
passages and stairs. The scraper and scraper blade may also be used as a tool in gardening
or earthworks for levelling soil for lawn groundwork or the bedding sand for paving,
for example. The scraper and scraper blade of the invention are light to use because
the curved portion of the scraper blade guides the amount of snow or soil the scraper
blade scrapes so that it is moved or thrown in the direction to which the scraper
shaft points, instead of being piled up as a single thick drift or heap right in front
of the scraper blade.
[0007] The scraper of the invention which comprises a scraper shaft and a scraper blade
to be fastened to the shaft is characterized in that the scraper blade is a scraper
blade as claimed in any one claims 1 to 7.
[0008] According to an embodiment, the fastening structure for fastening the blade to the
shaft comprises a tubular portion, which is made as a single uniform structure with
the scraper blade and into which the scraper shaft is insertable for fastening the
scraper blade to the scraper shaft.
[0009] According to an embodiment, the concave side of the curved portion forms a front
surface of the scraper blade and the convex side of the curved portion forms a rear
surface of the scrape blade, the rear surface comprising stiffening elements for stiffening
the scraper blade.
[0010] According to an embodiment, the rear surface of the scraper blade comprises stiffening
ribs extending upwards from the bottom edge of the scraper blade for stiffening the
lower part of the scraper blade.
[0011] According to an embodiment, the curved portion of the scraper blade is arranged to
be in the shape of a circular arc having a radius of curvature of R50 to 150.
[0012] According to an embodiment, the scraper blade is a single uniform injection moulded
piece made of a plastic material.
[0013] According to an embodiment, the scraper blade is made of polypropylene or polyethylene.
Brief description of the figures
[0014] The invention is now described in closer detail in connection with preferred embodiments,
with reference to the accompanying drawings, in which:
Figure 1 is a schematic front view of a scraper blade;
Figure 2 is a schematic front diagonal view of the scraper blade of Figure 1;
Figure 3 is a schematic rear diagonal view of the scraper blade of Figure 1;
Figure 4 is a schematic end view of the scraper blade of Figure 1; and
Figure 5 is a schematic view of a scraper with a scraper blade of Figures 1 to 4 fastened
to a shaft of the scraper.
Detailed description of the invention
[0015] Figure 1 is a schematic front view of a scraper blade 3, Figure 2 is a front diagonal
view of the scraper blade 3 of Figure 1, Figure 3 is a rear diagonal view of the scraper
blade 3 of Figure 1, Figure 4 is a schematic end or side view of the scraper blade
3 of Figure 1 and Figure 5 is a schematic view of a scraper 1 with a scraper blade
3 according to Figures 1 to 4 attached to a shaft 2 of the scraper 1.
[0016] The scraper blade 3 comprises a curved portion 4 having a bottom edge 4' and a top
edge 4". The curved portion 4 has a concave side 5 or a concave surface 5 that forms
a front surface 5 of the scraper blade 3 and a convex side 6 or a convex surface 6
that forms a rear surface 6 of the scraper blade 3. The scraper blade 3 further comprises
a straight portion 7 that joins the top edge 4" of the curved portion 4. The straight
portion 7 of the scraper blade 3 that joins the top edge 4" of the curved portion
4 extends in a direction indicated by the concave side 5 of the curved portion 4.
The straight portion 7 of the scraper blade 3 ends at an end edge 7' of the straight
portion, the end edge 7' being thus oriented away from the concave portion 5 of the
scraper blade 3. The end edge 7' of the straight portion 7 forms the top edge 7' of
the scraper blade 3 and the bottom edge 4' of the curved portion 4 forms the bottom
edge 4' of the scraper blade 3. The scraper blade 3 further comprises a fastening
structure 8 arranged in connection with the straight portion 7, the shaft 2 of the
scraper 1 being attachable in connection with the structure for fastening the scraper
blade 3 to the shaft 2 such that the scraper shaft 2 points in the direction to which
the concave side 5 of the scraper blade 3 faces. The scraper shaft 2, in turn, provides
a holding point for using the scraper 1. The rear surface 6 of the scraper blade 3
further comprises first stiffening elements 9 extending from the bottom edge 4' to
the top edge 7' for stiffening the structure of the scraper blade 3. In the case of
Figure 3, said first stiffening elements 9 are stiffening ribs extending from the
bottom edge 4' of the blade 3 to the top edge thereof. Said first stiffening elements
9 could also extend only to a portion between the bottom edge 4' and the top edge
7' of the blade on the rear surface 6 of the blade 3. It is also possible that said
first stiffening elements 9 are provided on the front surface 5 of the scraper blade
3. Further still, the first stiffening elements 9 may have a shape different from
a rib-like shape.
[0017] Figure 5 is a schematic view of a scraper 1 having a scraper blade 3 of Figures 1
to 4 attached to the shaft 2 of the scraper 1, the scraper shaft 2 being oriented
to the direction pointed by the concave side 5 of the scraper blade 3. The scraper
1 shown in Figure 5 may be used e.g. as a snow tool, for example for removing a layer
of snow of some centimetres from pathways, such as pedestrian passages and stairs.
The scraper 1 may also be used as a tool in gardening or earthworks for levelling
soil for lawn groundwork or the bedding sand for paving, for example.
[0018] When the scraper 1 is being used, the bottom edge 4' of the scraper 3 is directed
downwards and held against the surface to be cleared of snow, for example, or to the
layer of soil being levelled. Next, the scraper 1 is drawn so that the concave side
5 of the scraper blade 3 moves forward to the direction pointed by the shaft 2 towards
the user of the scraper 1 and, when desired, past the user. When the scraper 1 moves
towards the user of the scraper 1, a portion above the bottom edge 4' of the scraper
blade 3 scrapes snow or soil from the ground. Guided by the concave surface 5 and
the straight portion 7 of the scraper blade 3', the portion of snow or soil scraped
by the scraper blade 3 moves or is thrown forward in the direction to which the shaft
2 of the scraper 1 points, the scraper blade 3 leaving behind a ground from which
snow is cleared or roughness levelled. When the scraper is being used and depending
on the dimensioning the scraper blade 3, snow to be removed may be thrown by the scraper
blade 3 over edgings forming the borders of a pathway as a result of the drawing motion
without the scraper having to be lifted at the side of the edgings over the edgings
for removing the snow from the pathway area entirely. Moreover, when the scraper is
being used for removing snow, one draw with the scraper allows the surface to be cleared
to be made cleaner than by using a street broom.
[0019] In the embodiment of the scraper blade 3 depicted in Figures 1 to 5, the fastening
structure 8 for fastening the blade 3 to the shaft 2 extends from the direction of
the top edge 7' of the blade 3 towards the curved portion 4, extending partly also
into the area of the curved portion 4 and comprising a tubular portion 10 of a solid
cross-section into which the shaft 2 is inserted for fastening the blade 3 to the
shaft 2. Said tubular portion 10 comprises rib-shaped protrusions 11 extending to
the inside thereof parallel with the tubular portion 10, the protrusions restricting
the cross-sectional area inside the tubular portion 10 and thus increase a force effect
acting in a press fit formed between the fastening structure 8 and the scraper shaft
2, the press fit keeping the tubular portion 10 and the scraper shaft 2 attached to
one another. If desired, the fastening of the blade 3 to the shaft 2 may be further
ensured for example by a screw to be screwed to the scraper shaft 2 through the wall
of the tubular portion 10 or by gluing the tubular portion 10 and the shaft 2 together.
[0020] Although in the embodiment of Figures 1 to 5, the tubular portion 10 has a substantially
constant cross-section in the longitudinal direction thereof, the tubular portion
10 could also have a cross-section that narrows evenly from the top edge 7' of the
blade 3 towards the curved portion 4. It is also possible to provide a fastening structure
8 in which a form-locking is provided between the blade 3 and the shaft 2.
[0021] Alternatively, the fastening structure for fastening the scraper blade 3 to the scraper
shaft 2 could be for example a shaped structure made to the scraper blade 3 to provide
a shape supporting the scraper shaft 2. Alternatively, the fastening structure for
fastening the scraper blade 3 to the scraper shaft 2 may comprise, either alone or
in combination with the above fastening structures, one or more holes made through
the scraper blade 3 or one or more thinned portions made to the scraper blade 3, through
which a fastening screw or bolt or a similar fastening member extending to the scrape
shaft 2 or even through it is arranged for fastening the scraper blade 3 to the scraper
shaft 2.
[0022] In the examples shown in the figures the fastening structure for fastening the scraper
blade 3 to the scraper shaft 2 is arranged in the centre of the scraper blade in the
width direction thereof, although the position of the fastening structure may also
differ from that shown in the figures. Hence the fastening structure is not necessarily
in the centre of the blade. Another possibility is to implement the fastening structure
so that the shaft sets into an inclined position with regard to an imaginary centre
line that runs from the bottom edge 4' to the top edge 7' of the blade 3. The shaft
2 may be arranged to the blade 3 also by articulation or the fastening structure itself
may comprise an articulated structure that allows the position of the scraper shaft
2 in relation to the scraper blade 3 to be adjusted.
[0023] In the embodiment of the scraper blade 3 shown in Figures 1 to 5, the rear surface
6 of the scraper blade 3 comprises second stiffening elements 12 implemented as stiffening
ribs directed from the bottom edge 4' of the scraper blade 3 towards the top edge
7' and extending at least on some distance to the curved portion 4 of the blade 3,
without necessarily reaching, however, the straight portion 7 of the blade 3. Alternatively,
the second stiffening elements 12 may begin at a distance from the bottom edge 4'
of the blade 3 and extend towards the top edge 7' of the blade 3. The second stiffening
elements 12 are arranged to stiffen the lower portion of the blade 3 structure particularly
in the vicinity of its bottom edge 4' that is set against the ground. The second stiffening
elements 12 could also be formed of some other than a rib-like structure. Moreover,
said second stiffening elements may be placed on the front surface 5 of the blade
3 and their shape may differ from a rib-like shape.
[0024] In the embodiment of the scraper blade 3 shown in Figures 1 to 5 the bottom edge
4' of the blade 3 comprises a straight portion 13 extending from the front surface
5 of the blade towards the rear surface 6. Said straight portion 13 forms a support
surface that allows the blade 3 of the scraper 1 to be firmly held against the ground
when the scraper 1 is being used. At the same time, an acute angle 14 is formed at
the bottom edge between the straight portion 13 and the front surface 5 of the blade,
the angle providing the blade 3 with a sharp edge 14 that efficiently separates the
portion of snow to be removed or the soil to be moved from the ground surface, snow
or soil remaining underneath the bottom edge 4' of the blade 3. Although the bottom
edge 4' of the blade 3 wears when the blade 3 is drawn on the ground surface, the
blade 3 still maintains the acute angle and thus sharpens itself when the scraper
1 is being used.
[0025] The curved portion 4 of the blade 3 is symmetrically curved, i.e. a portion curved
in the shape of a circular arc and comprising a curved portion corresponding to only
one radius of curvature of a circle. In that case the curved portion 4 of the front
surface 5 of the blade 3 may have a radius of curvature R of a circle which may be
R50 to 150, for example. The radius of curvature R corresponding to the curved portion
4 of the blade 3 and the centre point CP of the radius of curvature are schematically
shown in Figure 4.
[0026] The angle of the shaft 2 of the scraper 1 to the ground surface is important for
convenient and efficient use of the scraper. Since the straight portion 7 of the scraper
blade 3 joins the top edge 4" of the curved portion 4 parallel to the tangent of the
top edge, the angle of use of the shaft 2 of the scraper 1 is determined by the joint
effect of the radius of curvature R of the curved portion 4 on the scraper blade 3
and a sector angle SA covering the curved portion 4. Depending on the radius of curvature
R applied on the curved portion 4, the sector angle SA, whose centre point is the
centre point CP of the radius of curvature of the circle, may be 70 to 150 degrees,
for example, preferably 90 to 120 degrees. In that case the sector angle SA of the
radius of curvature R70, for example, may be e.g. about 100 degrees.
[0027] The scraper blade 3 together with all of its features presented above is preferably
a single uniform piece. The scraper blade may be made as a single uniform piece of
metal or a plastic material, for example. A scraper blade made of a plastic material
may be manufactured as a single uniform piece by injection moulding, for example.
When the scraper blade 3 is being made of a plastic material, the material to be used
may be e.g. polypropylene PP or polyethylene PE, such as a high-density polyethylene
HDPE, or some other plastic grade that sustains well impacts even at cold temperatures
or sub-zero temperatures.
[0028] In practise the design and dimensioning of the scraper blade 3 may vary in many different
ways. The width of the blade 3, i.e. the blade's dimension in a direction substantially
transversal to the direction between the bottom edge 4' and the top edge 7' of the
blade may vary from 200 to 700mm, for example, preferably from 350 to 600mm. The height
of the blade 3, i.e. the shortest distance between the bottom edge 4' and the top
edge 7' of the blade, in turn, may vary from 50 to 350mm. Hence a scraper blade 3
may comprise a curved portion 4 corresponding to a circular arc having a radius of
curvature R72, for example, with a sector angle of about 110 degrees, the width of
the blade being, at the same time, about 450mm and the blade's height about 150mm,
for example.
[0029] 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. Hence the scraper blade 3 could also be implemented
without the straight portion 7, the fastening structure 8 being in that case entirely
on the curved portion 4 of the scraper blade 3.
1. A blade (3) of a scraper (1), characterized in that the scraper blade (3) comprises
a curved portion (4) formed of a curved portion (4) corresponding to only one radius
of curvature of a circle, the curved portion (4) having a concave side (5) that forms
a front surface (5) of the scraper blade (3) and a convex side (6) that forms a rear
surface (6) of the scraper blade (3),
the curved portion (4) of the scraper blade (3) has a sector angle (SA) of 70 to 150
degrees in relation to a centre point (CP) of the radius of curvature (R) of the curved
portion (4),
a straight portion (7) joining a top edge (4') of the curved portion (4) parallel
to a tangent of the top edge (4'), the straight portion (7) extending in a direction
indicated by the concave side (5) of the curved portion (4) and comprising a fastening
structure (8) for fastening the scraper blade (3) and a scraper shaft (2) together
such that the scraper shaft (2) points in the direction to which the concave side
(5) of the scraper blade (3) faces.
2. A scraper blade as claimed in claim 1, characterized in that the fastening structure (8) comprises a tubular portion (10) formed as a single uniform
structure with the scraper blade (3) and into which the scraper shaft (2) is insertable
for fastening the scraper blade (3) to the scraper shaft (2).
3. A scraper blade as claimed in any one of the preceding claims, characterized in that the curved portion (4) has a concave side (5) forming a front surface (5) of the
scraper blade (3) and the curved portion (4) has a convex side (6) forming a rear
surface (6) of the scraper blade (3), the rear surface (6) comprising stiffening elements
(9, 12) for stiffening the scraper blade (3).
4. A scraper blade as claimed in claim 3, characterized in that the rear surface (6) of the scrape blade (3) comprises stiffening ribs (12) extending
upward from the bottom edge (4') of the scraper blade (3) for stiffening the lower
part of the scraper blade (3).
5. A scraper blade as claimed in any one of the preceding claims, characterized in that the curved portion (4) of the scrape blade (3) is arranged to be in the shape of
a circular arc having a radius of curvature (R) of R50 to 150.
6. A scraper blade as claimed in any one of the preceding claims, characterized in that the scraper blade (3) is a single uniform piece made of a plastic material by injection
moulding.
7. A scraper blade as claimed in any one of the preceding claims, characterized in that the scraper blade (3) is made of polypropylene or polyethylene.
8. A scraper (1) comprising a shaft (2) of the scraper (1) and a blade (3) of the scraper
(1) to be fastened to the shaft, characterized in that the scraper blade (3) is a scraper blade (3) as claimed in any one of claims 1 to
7.
1. Schild (3) eines Schabers (1), dadurch gekennzeichnet, dass der Schaberschild (3) umfasst
einen gebogenen Abschnitt (4), der aus einem gebogenen Abschnitt (4) gebildet ist,
der ausschließlich einem Biegungsradius eines Kreises entspricht, wobei der gebogene
Abschnitt (4) eine konkave Seite (5), die eine vordere Fläche (5) des Schaberschilds
(3) bildet, und eine konvexe Seite (6), die eine hintere Fläche (6) des Schaberschilds
(3) bildet, aufweist,
wobei der gebogene Abschnitt (4) des Schaberschilds (3) einen Sektorwinkel (SA) von
70 bis 150 Grad in Bezug auf einen Mittelpunkt (CP) des Biegungsradius (R) des gebogenen
Abschnitts (4) aufweist,
einen geraden Abschnitt (7), der sich mit einer Oberkante (4') des gebogenen Abschnitts
(4) parallel zu einer Tangente der Oberkante (4') vereinigt, wobei sich der gerade
Abschnitt (7) in einer durch die konkave Seite (5) des gebogenen Abschnitts (4) angezeigten
Richtung erstreckt und eine Befestigungsstruktur (8) zum Befestigen des Schaberschilds
(3) und eines Schaberstiels (2) aneinander umfasst, sodass der Schaberstiel (2) in
die Richtung zeigt, in die die konkave Seite (5) des Schaberschilds (3) zeigt.
2. Schaberschild nach Anspruch 1, dadurch gekennzeichnet, dass die Befestigungsstruktur (8) einen rohrförmigen Abschnitt (10) umfasst, der mit dem
Schaberschild (3) als eine einzelne einheitliche Struktur ausgebildet ist, und in
den der Schaberstiel (2) zum Befestigen des Schaberschilds (3) an dem Schaberstiel
(2) eingesetzt werden kann.
3. Schaberschild nach einem der vorstehenden Ansprüche, dadurch gekennzeichnet, dass der gebogene Abschnitt (4) eine konkave Seite (5) aufweist, die eine vordere Fläche
(5) des Schaberschilds (3) bildet, und dass der gebogene Abschnitt (4) eine konvexe
Seite (6) aufweist, die eine hintere Fläche (6) des Schaberschilds (3) bildet, wobei
die hintere Fläche (6) Versteifungselemente (9, 12) zum Versteifen des Schaberschilds
(3) umfasst.
4. Schaberschild nach Anspruch 3, dadurch gekennzeichnet, dass die hintere Fläche (6) des Schaberschilds (3) Versteifungsrippen (12) umfasst, die
sich zum Versteifen des unteren Teils des Schaberschilds (3) von der Unterkante (4')
des Schaberschilds (3) nach oben erstrecken.
5. Schaberschild nach einem der vorstehenden Ansprüche, dadurch gekennzeichnet, dass der gebogene Abschnitt (4) des Schaberschilds (3) so ausgebildet ist, dass er die
Form eines Kreisbogens mit einem Biegungsradius (R) von R50 bis 150 aufweist.
6. Schaberschild nach einem der vorstehenden Ansprüche, dadurch gekennzeichnet, dass der Schaberschild (3) ein einzelnes einheitliches Stück ist, das mittels Spritzgießen
aus einem Kunststoffmaterial hergestellt wird.
7. Schaberschild nach einem der vorstehenden Ansprüche, dadurch gekennzeichnet, dass der Schaberschild (3) aus Polypropylen oder Polyethylen hergestellt ist.
8. Schaber (1), der einen Stiel (2) des Schabers (1) und einen an dem Stiel zu befestigenden
Schild (3) des Schabers (1) umfasst, dadurch gekennzeichnet, dass der Schaberschild (3) ein Schaberschild (3) nach einem der Ansprüche 1 bis 7 ist.
1. Lame (3) d'un racloir (1),
caractérisée en ce que la lame de racloir (3) comprend
une partie incurvée (4) formée d'une partie incurvée (4) correspondant à un seul rayon
de courbure d'un cercle, la partie incurvée (4) ayant un côté concave (5) qui forme
une surface avant (5) de la lame de racloir (3) et un côté convexe (6) qui forme une
surface arrière (6) de la lame de racloir (3),
la partie incurvée (4) de la lame de racloir (3) a un angle de secteur (SA) de 70
à 150 degrés par rapport à un point central (CP) du rayon de courbure (R) de la partie
incurvée (4),
une partie droite (7) joignant un bord supérieur (4') de la partie incurvée (4) parallèlement
à une tangente du bord supérieur (4'), la partie droite (7) s'étendant dans une direction
indiquée par le côté concave (5) de la partie incurvée (4) et comprenant une structure
de fixation (8) pour fixer ensemble la lame de racloir (3) et un manche de racloir
(2) de sorte que le manche de racloir (2) pointe dans la direction à laquelle le concave
côté (5) de la lame de racloir (3) fait face.
2. Lame de racloir selon la revendication 1, caractérisé en ce que la structure de fixation (8) comprend une partie tubulaire (10) formée en une seule
structure uniforme avec la lame de racloir (3) et dans laquelle le manche de racloir
(2) peut être inséré pour fixer la lame de racloir (3) au manche de racloir (2).
3. Lame de racloir selon l'une quelconque des revendications précédentes, caractérisée en ce que la partie incurvée (4) présente un côté concave (5) formant une surface avant (5)
de la lame de racloir (3) et la partie incurvée (4) présente un côté convexe (6) formant
une surface arrière (6) de la lame de racloir (3), la surface arrière (6) comprenant
des éléments raidisseurs (9, 12) pour raidir la lame de racloir (3).
4. Lame de racloir selon la revendication 3, caractérisée en ce que la surface arrière (6) de la lame de racloir (3) comporte des nervures de raidissement
(12) s'étendant vers le haut depuis le bord inférieur (4') de la lame de racloir (3)
pour raidir la partie inférieure de la lame de racloir (3).
5. Lame de racloir selon l'une quelconque des revendications précédentes, caractérisée en ce que la partie incurvée (4) de la lame de racloir (3) est agencée pour avoir la forme
d'un arc de cercle ayant un rayon de courbure (R) de R50 à 150.
6. Lame de racloir selon l'une quelconque des revendications précédentes, caractérisée en ce que la lame de racloir (3) est une pièce unique et uniforme faite en matière plastique
par moulage par injection.
7. Lame de racloir selon l'une quelconque des revendications précédentes, caractérisée en ce que la lame de racloir (3) est en polypropylène ou en polyéthylène.
8. Racloir (1) comprenant un manche (2) du racloir (1) et une lame (3) du racloir (1)
à fixer sur le manche, caractérisé en ce que la lame de racloir (3) est une lame de racloir (3) selon l'une quelconque des revendications
1 à 7.