Apparatus for controlling the movements of a roller-like horizontal rotary washing brush in motor vehicle washing apparatus

In a portal-type washing arrangement for vehicles, one of the rotary mountings for a horizontal rotary washing brush is arranged at the lower end of a vertically downwardly hanging swinging arm. The upper end of the swinging arm is connected to a first carriage which is vertically displaceable on a vertical guide rail of the portal assembly. Disposed in the region of movement of the swinging arm is a switching arrangement which controls a control motor. The control motor is connected by way of flexible traction means to the first carriage and to a second carriage which is vertically displaceable on a further vertical rail on the portal assembly. The other rotary mounting of the washing brush is directly and rigidly connected to the second carriage.

FIELD OF THE INVENTION 
The invention relates to apparatus for controlling the movements of a 
roller-like horizontal rotary washing brush in a motor vehicle washing 
apparatus in which the vehicle to be washed is moved relative to a portal 
assembly and in which the rotary mountings which are provided at both ends 
of the horizontal washing brush are each vertically movably mounted by 
means of a respective carriage which is guided in a vertical guide rail, 
wherein the washing brush is additionally mounted in such a way that it 
can be deflected in the direction of movement of the vehicle against a 
return force, and wherein there is a switching arrangement which is 
dependent on the deflection movement of the washing brush and controls a 
control motor which acts on the carriages. 
BACKGROUND OF THE INVENTION 
In motor vehicle washing equipment, the vehicle is moved relative to the 
washing assembly, wherein either the vehicle is pulled through the washing 
assembly by means of a conveyor belt or a portal assembly which carries 
the washing brush is moved with respect to the stationary vehicle. In such 
arrangements, the horizontal washing brush, whose axis is arranged 
transversely with respect to the direction of relative movement must be 
lifted from its lowest position, in which it washes the front of the 
vehicle at the level of the bumpers, up to the level of the roof, and then 
is lowered again when washing the rear of the vehicle. In order to raise 
and lower the washing brush, the apparatus has a control motor which acts 
by way of a transmission means and drive rollers on a conveyor cable, 
chain or the like which is connected to the carriages of the washing 
brush. A control means which is dependent on the deflection movement of 
the washing brush is provided for controlling the control motor. 
Swiss Pat. No. 443 940 discloses apparatus of the above-indicated kind. In 
this known portal-type washing apparatus, the horizontal washing brush is 
mounted in a frame which is supported on respective sides in respective 
carriages which are pivotal about an axis extending transversely with 
respect to the direction of movement of the portal assembly. The frame has 
switching cam members which co-operate with a limit switch disposed on the 
carriage. As long as the horizontal washing brush is not in contact with 
the vehicle, the two pivot arms which form a part of the frame hand 
vertically downwardly. As soon as the vehicle bears against the brush, the 
frame is pivoted about its horizontal pivot axis and the cam members 
actuate the limit switch. The limit switch switches on the control motor 
and causes the washing brush to be lifted, together with the frame. 
Instead of the switching cam members, it is also possible to use a 
plurality of switches which can be actuated by permanent magnets. A 
disadvantage with these known arrangements is that a relatively stable 
frame comprising two pivot arms and a transverse yoke member must always 
be provided, with the frame being supported at both sides in a respective 
carriage for pivotal movement about a horizontal axis. The frame must be 
of a stable construction because it must carry the weight of the 
horizontal washing brush and also carry the forces acting thereon. 
The invention is based on the problem of providing apparatus for 
controlling the movements of a roller-like horizontal rotary washing brush 
in vehicle washing equipment of the above-indicated kind, wherein the 
means supporting the brush are of a substantially simpler construction. 
SUMMARY OF THE INVENTION 
According to the invention, this is achieved in that only one of the rotary 
mountings is arranged at the lower end of a vertically hanging swinging 
arm, the upper end of which arm is connected to a carriage for pivotal 
movement about a horizontal pivot axis member which extends substantially 
parallel to the axis of rotation of the brush, while the other rotary 
mounting is rigidly connected to the associated second carriage, and in 
that a switching arrangement is disposed in the region of pivotal movement 
of the swinging arm or in the region of rotary movement of its pivot axis 
member. 
This arrangement provides for a substantial simplification in the apparatus 
for controlling the movements of the washing brush. At one end, the 
washing brush is mounted directly in the associated carriage. With this 
arrangement, it is possible to omit a frame which connects the two 
carriages and which carries the washing brush. The omission of a pivotal 
frame for carrying the brush also reduces the manufacturing costs of the 
apparatus. Furthermore, the lack of the pivotal frame also has an 
advantageous effect for reasons of space. In addition, it was surprisingly 
found that the washing brush which is mounted so that it can be deflected 
only at one side provides for more precise switching functions and thus 
quickly and precisely follows the contour of the vehicle to be washed. 
An advantageous embodiment of the invention provides that the distance of 
the pivot axis of the swinging arm from the axis of rotation of the brush 
is less than the radius of the brush. It was found that, with this 
construction, the means for controlling the movements of the brush 
operates with a very high degree of accuracy and the washing brush quickly 
and precisely follows the contours of the vehicle to be washed. This is 
evidently because, when the swinging arm is of a comparatively short 
length, the return force produced by the force of gravity, for returning 
the washing brush, rises rapidly when the swinging arm is deflected, and 
therefore, after the arm has been deflected and after the vertical 
position of the washing brush has been corrected by the control motor, and 
swinging arm is also rapidly returned to its starting position. It then 
remains in its starting position, in a comparatively stable manner, as 
long as the washing brush is not subjected to any displacement forces 
caused by the contour of the vehicle. 
It is also desirable for the swinging arm to be additionally held in its 
vertically hanging starting position by the return force of a spring 
assembly. This arrangement provides that the stabilizing effect of the 
short swinging arm is further enhanced. 
In addition, in another advantageous embodiment, it is advantageous for a 
rubber torsion spring which engages the pivot axis member of the swinging 
arm to be provided for returning the swinging arm to its vertically 
hanging starting position. The rubber torsion spring takes up a small 
amount of space and is also not liable to suffer from corrosion. The term 
rubber torsion spring in this context is used to denote a spring assembly 
comprising an outer ring and an inner ring which is arranged 
concentrically thereto, with rubber or rubber-elastic material disposed 
between the two rings and being vulcanised on to the two rings. The inner 
ring is non-rotatable with respect to the pivot axis member, while the 
outer ring is non-rotatable with respect to a housing.

DETAILED DESCRIPTION 
Referring to the drawing, reference numeral 1 denotes a portal assembly 
which is mounted on rails 2 for reciprocating motion in directions B and 
B1 (FIG. 2), by means of the travel motor 1b. Secured to each of the two 
vertical uprights 1a of the portal assembly is a respective vertical guide 
rail 3 in which a respective carriage 4 and 5 is mounted for movement in 
direction A (FIG. 1). One carriage 4 (the right-hand carriage in FIG. 1) 
is directly connected to the rotary mounting 6 of the shaft 8 of the 
horizontal washing brush 7. In the apparatus according to the invention, 
the carriage 4 may comprise a single roller. In contrast, the other 
carriage 5 (the left-hand carriage) is guided in the rail 3 by means of 
two rollers 5a. The carriage 5 carries the mountings 11 for a pivot axis 
member 12 which is connected to the upper end 13a of a swinging arm 13 
which, in the starting position, hangs vertically downwardly. A rubber 
torsion spring 14 also engages the pivot axis 12 of the swinging arm 13, 
the return force of the spring 14 urging the swinging arm 13 into its 
vertically hanging starting position. In this arrangement, the return 
force of the rubber spring 14 assists the return force caused by the force 
of gravity. 
The transmission means 9 of the motor 10 for driving the brush 7 is 
flange-connected to the lower end 13b of the swinging arm 13. The 
transmission means 9 also simultaneously includes the second rotary 
mounting for the shaft 8 of the brush. The distance a of the pivot axis of 
the member 12 from the axis 8a of rotation of the brush 7 is desirably 
less than the radius R of the brush. The distance a may be 1/2 to 2/3 of 
the radius R of the brush. 
Two cam discs 15 and 16 which co-operate with switches 17 and 18 on the 
carriage 5 are also disposed on the pivot axis member 12. The cam discs 15 
and 16 in this arrangement are of such a form that neither of the switches 
17 and 18 is actuated when the swinging arm 13 is in the vertically 
handing position. 
Each carriage 4 and 5 is also engaged by a toothed belt 23 (or a chain or a 
traction cable). Each of the toothed belts 23 is passed over a pinion 20 
which is arranged on the control shaft 19. A counterweight 21 is suspended 
on the second end of each toothed belt 23 in known manner, for 
compensating for the weight of the washing brush 7 and the parts which are 
connected to the washing brush, such as the drive motor 10, the 
transmission means 9 and the carriages 4 and 5, except for a residual 
weight of about 2 to 6 kg. The control shaft 19 is driven by means of a 
control motor 22, by way of an interposed transmission means (not shown) 
and free wheel. The nature of this drive means is described for example in 
DAS No. 25 18 718. The control motor 22 is controlled by the cams 17 and 
18. In practice, generally contact-less switches, such as for example reed 
contact switches which are controlled by means of permanent magnets, may 
be used instead of switching cams 15 and 16. 
OPERATION 
The mode of operation of the novel apparatus is as follows: 
As long as the washing brush 7 is only rotating and is still not in contact 
with the vehicle to be washed, the washing brush 7 is in the position 
shown in FIGS. 2 and 3 in solid lines, with the swinging arm 13 hanging 
substantially vertically downwardly. When now the portal assembly moves 
towards the left in the direction indicated by arrow B in FIG. 3, the 
washing brush 7 comes into contact with the vehicle F. As soon as the 
pressure applied to the vehicle by the brush exceeds a value which is 
determined by the spring assembly 14, the swinging arm 13 is pivoted 
towards the right, in the direction C. This causes the switching cam of 
the cam disc 15 to come into contact with the switch 17 which then starts 
the motor 22. The motor 22 now causes the carriages 4 and 5 and the 
washing brush 7 carried thereby, to be lifted, by way of the pinion 20 and 
the two toothed belts 23. The lifting movement continues until the brush 
has been lifted over the vertical front part of the vehicle F, whereupon 
the pressing force on the brush 7 in the direction B decreases again and 
thereby the swinging arm returns to its vertically downwardly hanging rest 
position, under the influence of the force of gravity acting on the brush 
7, the transmission means 9 and the motor 10, assisted by the return force 
of the spring assembly 14. This causes the cam disc 15 to return to its 
starting position shown in FIG. 3, and the switch 17 is no longer pressed. 
The arrangement could be such that, when the switch 17 is not pressed, the 
motor 22 is stopped. It is better, however for the motor 22 to be reversed 
so as to rotate in its opposite direction, which causes the brush to be 
lowered, and to continue to be driven in that direction while the switch 
17 is not pressed, in accordance with the control action described in DAS 
No. 25 18 718. For that purpose, it is then necessary to provide a free 
wheel assembly between the control motor 22 and the control shaft 19, the 
free wheel assembly releasing the drive connection between the control 
motor 22 and the control shaft 19 as soon as the control motor 22 is 
driven in the `lower` direction of rotation and as soon as the output 
shaft of the motor is rotating at a higher speed than the control shaft 
19. Conversely, the free wheel assembly locks as soon as the control motor 
22 is driven in the `raise` direction of rotation. 
The cam disc 16 shown in FIG. 1 has switching cams on both sides, which 
come into contact with the switch 18 only when the swinging arm 13 or the 
pivot axis member 12 has moved through a large angle of pivotal movement. 
A greater deflection movement of the swinging arm 13 occurs, for example, 
when the portal assembly 1 is moved at an excessively high speed in the 
direction B relative to the vehicle to be washed, and the control motor 
cannot raise the washing brush sufficiently quickly or sufficiently far. 
This situation occurs in particular if a larger, vertical or approximately 
vertical front surface of a vehicle has to be washed, such as for example 
the front of a VW transporter or bus. In this case, the switch 18 is 
pressed by the switching cam of the second cam disc 16 and stops the 
travel motor 1b of the portal assembly, while the control motor 22 
continues to be driven in the `raise` direction of rotation. The travel 
motor 1b of the portal assembly is stopped until, when the washing brush 
reaches the upper edge of the vertical surface of the vehicle, the 
pressure as between the brush and the vehicle decreases again and the 
swinging arm 13 is returned to its vertical starting position. 
In portal-type washing arrangements in which the portal assembly 1 is moved 
and the vehicle is stationary, the portal assembly is first moved beyond 
the vehicle in one direction, and then the direction of movement of the 
portal assembly is reversed and the vehicle is washed again in the 
opposite direction. This means that, after the vehicle F has been washed 
in the direction of movement B, the portal assembly is reversed in its 
direction of movement and moves in the direction indicated by arrow B1. As 
soon as the pressure between the washing brush 7 and the vehicle exceeds 
the set value, the swinging arm 13 is pivoted in the opposite direction C1 
and the control motor 22 or the travel motor 1b are then controlled by 
means of the cam discs 15 and 16 respectively, when the portal assembly is 
moving rearwardly in direction B1, in the same manner as when the portal 
assembly was moving forwardly in direction B. 
Use of the novel apparatus is not restricted to portal-type washing 
arrangements in which the portal assembly is moved backwards and forwards 
and the vehicle is stationary during the washing operation. The novel 
apparatus can equally well be used for a washing arrangement in which the 
vehicle passes through, wherein the portal assembly is rigidly mounted and 
the vehicle is drawn through the portal assembly by suitable conveyor 
means. 
In addition, switching cams or switch actuating means may also be arranged 
directly on the pivoting arm. 
Instead of a control arrangement with a free wheel assembly, it would also 
be possible to use a control arrangement without such a free wheel 
assembly. In that case, the switching arrangement would be so designed 
that, when the swinging arm is in the vertical position, the control motor 
is driven in the `lower` direction of rotation. If the swinging arm were 
to be slightly deflected from its vertical starting position, the control 
motor would be stopped, corresponding to a second position of the cam disc 
15. If the swinging arm were subject to a greater degree of deflection, 
the control motor would be driven in the `raise` direction of rotation, 
while, if the swinging arm were pivoted through an extremely large angle, 
the travel motor of the portal assembly would additionally be stopped, as 
described above.