Note: Descriptions are shown in the official language in which they were submitted.
CA 02227242 1998-01-19
W097/03867 PCT~096/00188
DEVICE FOR REMOVING ICE AND/OR SNOW
FROM WINDOWSCREEN WIPERS
The present invention relates to a device for removing ice and/or snow from wintlehielcl
S wipers, particularly for use on relatively heavy vehicles, in accordance with the
preamble of claim l.
A number of devices of this type are known. Among these are the one described in US
2,784,438. Here, there is shown a device which raises the winllehielcl wiper up from the
10 window, in order thereafter to release the wiper so that snow and/or ice is knocked off
the wiper blade. The lifting of the wi . .flsl ~ ield wiper arm is brought about by means of a
solenoid mounted on th~e arm and o~.dli~,e b~ a r~ ..;..g means for the solenoidand a bracket on the wiper arm. As is known, the solenoid is electrically po~ l This
implies that it must be well sealed in order to prevent moisture and/or dust from
15 pel~ dlillg into the meçh~niem and ;Illl-Ail ;1)~ its function as, for eY~mple, in the case of
a short circuit.
Further, a special bracket must be c~eei~npd for the windshield wiper arm; this
neceSsit~tre the repl~r.oment of the windshield wiper arm in cases where the solenoid is
20 to be mounted after delivery on a vehicle which has not been equipped with such a
device from the factory. For this reason the device also becomes very c;Al~c~ e for
post-delivery in~t~ tion-
US 4,309,789 also shows an d~Jaldlus that utilizes co...~lessed air to remove ice and/or
25 snow from the windshield wiper blade. Here, co..-~-essed air is supplied to an internal
duct running along the length of the windshield wiper blade, which causes the
windshield wiper blade to inflate, almost like a balloon, and the snow and/or ice will
thereby be loosened. In this case, however, there will be need for a very special
win-l~hielcl wiper blade, which would be ~ A~ll~iV~ to replace.
The wiper blade will also be quite vulnerable to ~m~ge, since merely a single crack
~ e~ctt-n-iing from the surface of the blade into the duct will puncture the duct and
impair the snow and ice removing ~lnrtiorl Con~ prin~ how frequently it is nece~to change a common windshield wiper blade, this device would have to be very
35 ullcconolllical for use over a long period oftime.
With the present invention, we seek to provide a device that is simple to mount after the
vehicle has left the factory, is not dependent on electric or electronic co...polle.l~
CA 02227242 1998-01-19
W O 97/03867 PCTA~096/00188
disposed on the outside of the vehicle, and is reasonable to procure and reliable to
operate. This is achieved by the features disclosed in the ~hs..",;~.;,;,,g clause ofthe
following claim 1.
S Further embo~1im~ntc are disclosed in the subse4u~lll dependent claims.
The invention will now be described in more detail with lef.,~cnce to the accolllpdllyillg
~awill~s, where
Figure 1 is a side view of the device, from a first direction,
Figure 2 is a side view of the device, from a direction perpendicular to t_e first
direction,
Figure 3 is a top view of the device,
Figure 4 is a cross-sectional view of the device, and
Figure 5 is a view of the device mounted in conjunction with a windshield wiper arm.
The device 1 is shown in Figures 1 and 5 mounted in co",.~cli~ n with a windshield
wiper arm 20, w_ich is illu il~dl~ in cross section in Figure 1. The device conci ctc of a
housing 2 and a foot 3. Projecting from an o~ .fillg 4 at the top of hol~cing 2 is a piston
S (see Figure 4). Fastened to the top of piston S by means of a screw 6 is a lifting hook
7. The lifting hook 7 is provided at its o-lt~rmost end with a lifting member 8.
Inside housing 2 on one of the sides of piston 5 is formed a high ~les~ , chamber 9,
and on the other side of piston 5 is formed a low plC~UlC chamber 10. High pl~
~ h~mh~r 9 is supplied with co.l.p.essed air via a cO--l~ ~,ssed air duct 11. In low
~JlC~ ;; chamber 10 is position~cl a return spring 12, which urges piston 5 into housing
2 when the col.lp.cssed air in high ~ h~mher 9 is l~ ce.l An O-ring seal 13
ensures that dust and moisture do not penetrate into housing 2.
As illustrated in Figure 5, the device 1 may be placed with foot 3 against the body 21 of
a vehicle. Device 1 is arranged such that li~ng member 8 is c~ te<l llnc1Prn~th a
section of windshield wiper arm 20. ~lt~rn~tively, the entire device, if space permits,
may be placed b~Lwccll the vehicle body 21 and the win~lchiel<l wiper arm 20. Then the
CA 02227242 1998-01-19
WO 97103867 PCI~/N096/0018
screw 6, or optionally a suitable striking member mounted thereon, will form the thrust
surface against the wiper arm 20.
The cu~ ed air duct 11 may be co....~ cl in a practical manner via a suitable valve
- S (not shown) to a colllpre~ed air system already eXiCtin~ in the vehicle. The valve may
be, for PY~mple, electrically ~ Lcd and may be .Cit~-~t~1 inside the driver's cabin.
When lumps of ice or clurnps of snow begin to form on the w;~ h;clcl wiper blade 22,
the vehicle driver may operate a switch, pl~.ably several times in ~Iccec~i~ n, and
thereby send a plurality of colll~l.,.,.,ed air pulses to the high ~ UICi ch~mh~r 9. The
piston will thereby be thrust out of the housing with great force, and will thus lift the
wiper arm 20, thereby bringing wiper blade 22 out of contact with the window pane 23.
The return spring 12 will ensure that the piston 5 is returned to its original position in
housing 2 when the pl~SS:~ul~, in high pl~.7UI~ ~h~rn~,r 9 has dlu~ ed sl~ffisi~ntly. A
plurality of ~ec~ ; v~; oper~tioll~ of the valve will cause piston 5 to be lifted and
returned to its original position several times in s~lcce~ion, and ice and snow will
thereby be knocked offthe windshield wiper blade 22 in a very effective mZ~nn~.r~ as the
blade repeatedly strikes against the window pane 23.
In vehicles without an internal compressed air system, a small co-..~ ssor must be
20 mounted after delivery for the operation of the ice/snow removal device. Optionally the
device may also be de~ign~d for ~ hl.lc.,l to a vacuum, e.g., the vehicle's vacuum
brake booster. In that case, the v~.;uum will have effect on the low p.~ , chamber
10, while the high lnc.,~ ch~rnhPr 10 l~,.llains below ~trn(l~rh~ri~
25 Piston 5 may also be ~ ignP$1 with adjustable length to adapt to various spacing
relationships between the vehicle body and the wiper arm. The device may also beadhered securely to the vehicle w~w pane and thereby be c ~ live between the
window pane and the wiper arm, or it may be;, .f. ,~1 ~t~ cl into the vehicle body with
factory in~t~ tio~ The device co.ll~ol~-ll~ could basically be made of plastic, e.g.,
30 POM.
