Note: Descriptions are shown in the official language in which they were submitted.
~ 2i25~6
940609PC2601 - 1 -
Vacuum Mower with a device for Creating a Suction Air Stream
This invention concerns a vacuum mower according to the
general terms of claim 1. By vacuum mower are understood all
grass mowing devices that use an air stream, in whichever way,
to support the mowing process. Vacuum mowers are conventional
mowing devices, as eg. the ones in DE B1 2643604 DE B1 shows
a suction tube with an opening for the intake as well as one
for the exhaust with a suction/blowing device which is able to
suck the grass into the casing. According to DE B1 the device,
contrary to other conventional mowers with rotating blades
that operate parallel to the ground as, for example the US A
4718221, has the advantage that the angle between the opening
for the intake and the direction of the growth of the grass
can be altered. The mowing device for cutting the stems of the
grass may be placed in front of the opening for the intake in
the shape of a chaff cutting cylinder within a suction bell
(column 1, lines 60-64), but it may also be built into the
device directly at the intake in the form of a nozzle sucking
up the grass (column 3, lines 63-64).
Chaff cutting cylinders are unshapely cylinders with a large
number of cutting blades which are used only for a special
mowing process of large areas. Their drives though, are heavy
and cylinders serve for cutting the grass into small pieces
rather than for cutting it off neatly. Placing the cutting --
device at one end of the suction tube while the other is
mounted on a vehicle held above the ground by wheels,
regardless of the contour of the ground below the cutting
device, makes the construction somewhat difficult if you want
to cut the grass at always the same height above the ground.
The suction tube is rarely used for cutting grass on uneven
terrain because it was mainly constructed for cutting bushes
and shrubs at the side of the road, respectively for cutting
grass on ground sloping down to the road. Such known devices
are less suitable for universal use in gardens, parks or, for
example golf courses.
212~9~ 6
940609PC2601 - 2 -
The main purpose of the invention is to devise a simple vacuum
mower for universal use that can mow grass at an angle to the
vertical as can chaff cutting cylinders, so that, for example,
also the edges of an even meadow that do not lie directly
below the mower can be trimmed, the mower following by itself
the contour of the ground below. -
This task is essentially achieved by combining the following(see claim 1):
A device for always maintaining the same distance from the
ground (e.g. in accordance with US A 5020309)
- ~
Placing the intake opening at an angle (as in DE Bl
2643604) and
Use of a device creating a vacuum strong enough to bend
and suck grass from around the intake opening into the
casing so that it may be cut there.
The invention may be used independently or in combination with
conventional lawn mowers, particularly to remowe grass from -~ ~;
the areas next to stable obstacles in the best way possible~
Because of this, trimming these areas by hand or with hand-
held cutting devices after the use of the mower can become
unnecessary.
,
This also has the special advantage of approaching the grass
that has to be cut from the side without directly touching it.
With this invention the grass, so to speak, moves towards the
mowing device whereas with the conventional lawn mowers, as
for example according to US A, the mowing device has to be
moved towards the grass, respectively must be put on top of
it. A further result is a relatively low wear of the mowing
equipment, but in particular a protection of bushes, bark of
trees, facades, etc. because these will come in contact with
only the vacuum stream during the mowing procedure and will
212S95 6
940609PC2601 - 3 -
not automatically be engaged and cut or at least damaged as is
the case with conventional chaff cutting devices.
By preferrential design of the cutting tool according to claim
5 2, either the vacuum generator or a separate drive for the ~
cutting tool can-be omitted (possibility according to claim ~-
3).
Though with some conventional lawn mowers attachments
lo resembling ventilators are known to exist, these serve to
collect the cut grass for example in a bag or to maintain a
steady distance from the ground without using a wheel, by
creating a sort of an air cushion. The sucking in of the grass
at an angle different from the direction of the growth of the
lS grass as is the case in the concept according to DE Bl however
is impossible.
The lawn mower described in US A 5020309 also has an
additional ventilator in the grass discharge conduit in order
20 to discharge cut blades of grass from the mower and to perhaps `
shred them. This mower can follow contours of the ground well,
due to its wheels, but cannot cut grass at the edges or around
trees, next to waIls, etc. in a satisfactory manner because
this grass - as with all other conventional mowers - is not
grabbed and therefore not cut either. For the grass growing in
such spots, special cutting devices such as weed eaters,
trimmers and hedgers have been designed, which will be
rendered obsolete by this invention.
Thus conventional lawn mowers, with blades that create an air
stream, differ only slightly from other lawn mowers - at least
in regard to their capability to engage and grab blades of
grass etc. close to walls, tree trunks, roots, bushes, fences,
poles along roads, etc. For cutting off of grass close to such
more or less stable obstacles, conventional lawn mowers (with
the exception of motor scythes) can hardly be used. For one
wheels, protective parts and other parts of the frame of the
lawn mower are not allowed to get close to said obstacles and,
2125'g.5'~
940609PC2601 - 4 -
in addition mowing around posts along the side of roads is
often cumbersome and impeded by buildings.
In these cases the suction effect of conventional lawn mowers
is practically useless because the area where they can
effectively be used is hardly larger than the one lying
directly under the mower. Further characteristics and details
as well as various types of the invention are described in the
relevant claims.
m e different ways of using the invention have the following
advantages~
At an angle of application of not more than 80 degrees, the ~ -
suction power reaches beyond the area of the lawn mower proper
and may suck in and cut off for example small grass blades,
bushes, etc. in a direction about parallel to the ground. By
standard direction of growth essentially a vertical direction
to the ground is unders~ood. Above all, longer blades of grass
whose stem is relatively thick close to the ground are cought
by the invention at the top where they can still be easily
bent, and be pulled into the lawn mower where they are cut
off.
The smaller the angle of application, the closer it is to 0
degrees, the stronger is the vertical effect on the ground
with the lawn mower of this invention. So, for example even
grass blades around a roadside pole can at the same time be
pulled in by the vacuum stream and be cut off. Mowing around
such a pole thus is not necessary. Practical application shows
that the resulting small differences in the length of the cut
stems of grass are tolerable.
Mounting the invention on a conventional lawn mower results in
an advantageous combination with which grass can be
successfully cut wherever it may grow. In addition, it is
possible to pick up leaves, etc. as with a vacuum cleaner for
which purpose a detachable suction bell may be provided.
212S9~6
940609PC2601 - 5 -
- .
The exact spot where on a conventional lawn mower the
invention may be mounted can be freely chosen. One may
paritcularly choose to place it between the front or the back
wheels. The invention may also be completely integrated into
the casing of the lawn mower. In that case, placing it in the
area of the felloe of the wheels provides a particularly
elegant and compact solution.
Mounting the invention on a cutting device with open blades
results in an even more flexible use in the niches in walls,
etc. in which case especially the suction effect turns out to
be an asset in supporting the mowing process.
The use of a tubular casing complies with the rules of the use
of rotating blades and devices for the creation of an air
stream (e.g. ventilator blades). In that case the discharge
opening is designed so that on the one hand the cut off grass
is discharged in the best way possible and on the other hand
there is no contact with rotating parts on the discharge side
of the machine.
Of course other blades or air stream creating devices as, for
example the radial cylindric blower type, lie within the scope
2S of the invention.
A device to protect direct touch of the intake opening
prevents the intake of stronger bushes which are not meant to
be cut, as well as injuries of hands or pets.
The variant with a friction clutch increases the safety of the ;~ -
device and prevents the killing of the respective motor.
The design according to claim 2 in one piece is very compact
and has only few individual parts. The adjustable cover of the
intake opening makes it possible to regulate the power of the
air stream and protects the rotating blades.
. ~
~` 21259~
940609PC2601 - 6 -
The safety i8 further increased by the measures of claim 10.
The type according to claim 3 is a design without a separate
motor for the cutting device and at the same time has-a
friction clutch effect at the cutting part. There the cutting
apparatus has to be in relative proportion with the diameter
of the suction tube as well as with the force of the air
stream. This solution provides the advantage of separating the
motor generating the air stream from the area where the grass
is cut. Placing this mowing device in the suction nozzle in
accordance with DE Bl would be feasible.
The invention is further explained by the enclosed drawings,
which show in
Fig.l and 2 the invention attached to a conventional lawn
mower;
Fig.3 and 4 a suction mower (vacuum mower) using the
invention as may be the case with motor
scythes;
Fig.S and 6 a device for mowing edges of roads; and
Fig.7 a detail of the attachement of the invention
to a conventional lawn mower being used to mow
around a roadside post.
The drawings are described in context and in an overall way.
Same parts are marked by same symbols, similar parts show same
symbols but are indexed differently.
The invention is best used for the mowing of grass along walls
and fences and around trees, bushes, roadside posts 1 etc. By
obliquely adjusting the intake opening 16 (fig.3) grass 14 is
pulled vertically into the intake opening 16 and is cut there
by a cutting device 7. A casing 6 built around the cutting -
device 7 is designed for either the axial discharge of the
grass (6a according to fig.1-4 and 7) or for the radial -~
discharge of the grass (6b according to fig.5 and 6).
~125'9~;6
940609PC26dl - 7 -
Attaching a vacuum mower as in the invention to a conventional
lawn mower 3a (fig.1 and 2) is best used for mowing larger
areas and only in second place in removing grass 14 close to
walls 1. In that case a conventional lawn mower 3a is-slid or
pushed - as usual - over the mower by means of a sliding guide
2a.
The casing 6a is mounted in such a manner that the intake
opening 16 can be positioned close to the wall 1. Mounting is
by fitting 5 which is adjustable and slides into desired
position so that the mower can be adjusted as conditions may
require.
~y such a fitting, particularly 5, the angle of the intake
opening too may be adjusted.
In the case of fig.1 and 2 the power from the motor of the
conventional lawn ~ower 3a is transmitted to the vacuum mower
as in the invention by a belt or a flexible shaft 4a. In the
other cases, the power is generated by a motor 4b driven by
combustion, electrically or hydraulically or by a vacuum air
current, etc.
The intake opening 16 is protected against direct contact by a
protective grill 8, so tha~ voluminous objects can be kept
away from the cutting device.
The type in fig.5 and 6 is a special design for mowing close
to road edges, walls, fences, etc. There the discharge opening ; -
17b goes into a bagging device or into a basket. Through a
removable covering 9 the diameter of the intake opening 16 can
be varied in order to regulate the suction power. The intake
opening may be rotated around a rotation point 10. Within the
frame of the invention lie also other types of covers such as
sliding metal plates, etc.
212~9~
940609PC2601 - 8 -
The type for mowing road edges 3b can be pushed on wheels 12, -
the height of which is adjustable. It can be directed by push ~ -~
bars 2b.
The type according to fig.7 shows the assembly of a lawn mower
with the vacuum mower attached according to the invention for
mowing relatively large areas 14 at the edges of roads 15
respectively next to the road surface itself 13. Contrary to
the type as according to fig.1 and 2 such a vacuum mower has
lo its own, for example hydraulic motor 4b which, for example
allows for the regulation of the vacuum power by the speed of
rotation. Such devices are, for example frequently mounted on
communal riding mowers. The fixing 5 may, for example be
adjusted or hydraulically turned along the arc marked by
points and dashes around the lawn mower 3b. By doing this all
possible special situations at a given edge of a road can be
met. An elegant solution can be seen in fig.3 where the intake
opening has been integrated in a wheel 12a.
Special safety devices to reduce the danger of injuries of the
user, of animals, etc. respectively to protect the blades (in
case of the use of an idling device) are not shown in the
drawings but may be provided as described in the claims. The
invention may also be used to its advantage as a blower or for
collecting fallen leaves. In the first case a device for the
reversion of the sense of rotation can be installed. If the
discharge opening of the case of the cutting device leads to
the mower deck of a lawn mower as shown in the drawing, there .
is the additional advantage of the grass being shreded once
more and is at any rate taken through the mower to, for
example a bagging device or grass collection basket.
21 2~95 G
940609PC2~01 - 9 -
List of Symbols
1. Wall, tree, bush, garden fence, roadside posts
2a. Guiderail to mount mower
2b. Push bars
3a. Lawn mower or æimilar device
3b. Device for mowing road edges
4a. Transmission by belt, flexible shaft, etc.
5. Fixing (adjustable or sliding in all directions)
6a. Casing for axial discharge
6b. Casing for radial discharge
7a. Ventilator (blades) including cutting device for axial
discharge
7b. Ventilator (blades) including cutting device for
lS radial discharge
8. Protection grill
9. Adjustable cover (for less suction or greater safety)
10. Pivot for cover
11. Collection bag or basket
12,12a. One or several wheels the height of which can be
adjusted
13. Road surface
14. Grass
15. Road edge
16. Intake (opening)
17a,b. Discharge (opening) ~ ;
