BACKGROUND OF THE INVENTION Many automatic car wash installations use rotating brushes to clean the surfaces of vehicle. Some installations employ separate brushes to clean each side of the vehicle, and additional brushes to clean the front and rear of the vehicle.

There has been some effort made to develop car wash apparatus in which a single brush can clean the front, rear and one side of the vehicle. This type of apparatus has become known as a wrap- around brush assembly, or a wrap brush assembly for short.

In a typical wrap brush apparatus, a pair of rotary brushes, or wrap brushes, are carried on arms positioned in sequential order on opposite sides of the track along which the vehicle is moved. Generally, the wrap brush itself consists of a rotating shaft having numerous lengths of fabric secured thereto. As the brush shaft rotates, the lengths of fabric are extended outwardly by centrifugal force to contact the surfaces of the vehicle.

As the vehicle passes along the track, the arms are moved so that each of the brushes will first contact the front of the car and then scrub laterally and outwardly from the center of the car towards one side. As the vehicle continues to move, the brushes will contact the side of the car and finally will return towards the center of the car and scrub the back or real of the car in doing so.

Examples of vehicle washing systems incorporating a pair of rotating wrap brushes that rotate about vertical axes are shown in U. S. Pat. Nos. 3,471, 883; 4,198, 722; 4,225, 995; 4,270, 958; 4,299, 003; and 4,354, 291, all issued to Ennis; U. S. Pat. No.

4,359, 796 issued to Holbus et al; and U. S. Pat. No. 5,715, 558 issued to Johnson.

Typically, these rotating wrap brush assemblies are supported from an overhead support structure, such as an overhead support arm. The overhead support structure is capable of pivoting through a horizontal arc to allow the wrap brushes to move from side to side, relative to the direction of vehicle travel through the washing apparatus.

This side to side movement allows the wrap brush assembly to move across the front, side, and rear surfaces of the vehicle as the vehicle is moved past the wrap brushes.

One type of overhead support structure consists of a pair of series-connected arms, including a first arm pivoted from a fixed overhead bridge, and a second arm pivoted from the free end of the first arm. The rotating wrap brush is suspended from the free end of the second arm. An example of such a two-arm overhead arm assembly is shown in the aforementioned U. S. Pat. No. 3,471, 883.

Such two arm support assemblies have generally been replaced by "single-arm"support arms, where the first end of the support arm is pivoted from the overhead bridge and the rotating warp brush assembly is supported from the free end of such overhead arm. An example of such a single-arm overhead support arm assembly is shown in the aforementioned U. S. Pat. Nos. 4,198, 722 and 5,715, 558.

Early rotating wrap brush assemblies maintained each wrap brush shaft along a fixed vertical axis so that the wrap brush was always perpendicular to the ground. The aforementioned U. S.

Pat. No. 3,471, 883 is an example of such a wrap brush assembly.

It was later discovered to be advantageous to allow the brush assembly to swing or tilt away from a perfectly vertical axis upon contacting the surfaces of the vehicle to assist in movement of the brush around the corners of the vehicle. One example of such brush assembly that includes wrap brushes allowed to swing or tilt is shown in the aforementioned U. S. Pat. No. 4,198, 722, which discloses the use of either a flexible elastic coupling or a flexible plastic brush shaft to permit the brush to tilt or swing upon impact with the surfaces of the vehicle. In addition, one embodiment, shown in figures 15 and 16 of the aforementioned 4,198, 722 patent shows a brush assembly pivot mechanism 130 to protect the vehicle and the brush assembly against damage in the event that the vehicle is inadvertently driven into the brush assembly when the wrap brush is not being rotated. Similarly, U. S. Pat. No. 4,354, 291 shows that a flexible spring coupling may also be used to couple the rotating brushes to the overhead support arms. These swing or tilt axis wrap brush assemblies have one thing in common-a single pivot axis for the wrap brush assemblies and are thus considered""single axis"wrap brush units.

Other support mechanisms for allowing a rotating wrap brush to swing or tilt away from a vertical axis have also been introduced commercially. For example, A. V. W. Equipment Co. , Inc. of Maywood, Ill. has offered its"Z-WRAP AROUND"wrap brush assembly with a flexible piece of belting or hose to support the rotating wrap brush from an overhead support arm, thereby allowing the rotating wrap brush to swing or tilt upon contacting the surface of a vehicle.

While single axis rotating wrap brush assemblies provide advantages over wrap brushes that can not swing or tilt, they also introduce a new problem. As the wrap brush contacts the rear surface of the vehicle, the rotating motion of the brush against the vehicle surface causes the brush to ride up along the rear

surface of the vehicle toward the center of the vehicle path. In some cases, this climbing action of the brush actually causes the brush to climb up upon the trunk or rear deck of the vehicle, wherein the brush axis is tilted from the vertical by 45 degrees or more. In these instances, the wrap brush can not effectively clean the rear surface of the vehicle.

To overcome this problem, some manufacturers have introduced a dual axis suspension system for the wrap brush assemblies. For example, the aforementioned U. S. Pat. No. 5,715, 558 issued to Johnson discloses a dual axis wrap brush assembly. This wrap brush assembly includes an elongated, horizontal upper support arm which pivots, from an overhead support about a vertical axis.

The horizontal upper support arm is substantially parallel to the path traversed by a vehicle being cleaned. A pivot link is pivotally connected to the free end of the upper support arm about a horizontal pivot link axis for movement forward and rearward relative to the path traversed by a vehicle to be cleaned. A brush support bracket is pivotally connected to the lower end of the pivot link about a horizontal pivot link axis lying perpendicular to the pivot link axis for allowing the brush support bracket to swing side to side relative to the path traversed by a vehicle to be cleaned.

This geometry provides the wrap brush assembly with two pivot points, allowing two directions of movement for the wrap brush. In theory, the horizontal upper support arms are parallel to the path traversed by a vehicle being cleaned. When in this parallel position, the pivot points allow the wrap brush assembly to move in: (i) a forward and backward direction parallel to the path traversed by the vehicle being cleaned; and (ii) a side to side direction perpendicular to the path traversed by the vehicle. Since the two pivot points are maintained perpendicular to each other, the two independent movements of the wrap brush

(forward and backward, and side to side) are necessarily perpendicular.

One drawback with this design is that not all vehicles being cleaned are the same width. If the horizontal upper support arms, and thus the wrap brush assemblies, are spaced for the average width vehicle, the horizontal upper support arms will be angled inward, and not parallel to the path traversed by the vehicle when narrow vehicles are cleaned, and angled outward, and similarly not parallel to the path traversed by the vehicle when wider vehicles are cleaned. Since the pivot link is attached to the horizontal upper support arm by a horizontal pin, it cannot rotate relative to the horizontal upper support arm, but instead is only free to swing in a direction forward and backward relative to the horizontal upper support arm. Accordingly, since the position of the horizontal upper support arm is something other than parallel to the path traversed by the vehicle being cleaned, the movement of the wrap brush allowed by the pivot link axis and bracket pivot axis cannot be maintained parallel (forward and backward) and perpendicular (side to side) as desired.

One consequence of this geometry is that when the wrap brushes are not free to move perpendicular and parallel to the direction of vehicle travel, extra force caused by the wrap brush swinging in angular relationship to the path traversed by the vehicle being cleaned are transmitted to the sides of the vehicles. In some instances, these forces are sufficient to damage the sides of the vehicles being cleaned, including breaking the side-view mirrors from their mounting brackets.

The disclosures of the aforementioned patents referenced in this background of the invention are herein incorporated by reference in their entirety.

What is needed is an apparatus capable of sufficiently cleaning the front, rear and sides of the vehicle, while still allowing adequate forward/backward and side-to-side movement of the wrap brushes to minimize damage.

SUMMARY OF THE INVENTION The instant invention discloses a coupling assembly for suspended cleaning brushes. The coupling assembly comprising a pivot element having a first and second end. The pivot element pivotally attaches the coupling assembly to an overhead support about a first pivot axis. A first receptor coupling is rigidly attached to the second end of the pivot element. The first end of a tension bar having a first and second end is pivotally attached to the first receptor coupling about a second pivot axis. The second end of the tension bar is pivotally attached to a second receptor coupling about a third pivot axis. A motor torque housing is rigidly attached to the second receptor coupling. The motor torque housing supports a motor for rotating the suspended brush.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 shows a side elevation view of the wrap brush assembly for cleaning the outer surface of a vehicle according to one embodiment of the invention.

Figure 2 shows a top view of the wrap brush assembly for cleaning the outer surface of a vehicle according to one embodiment of the invention.

Figure 3 is a perspective view of a typical connection between the overhead support arms and the bridge members according to one embodiment of the present invention.

Figure 4 is a perspective view of the triple axis coupling according to one embodiment of the present.

Figure 5A is a perspective view of the pivot element according to one embodiment of the present invention.

Figure 5B is a front elevation view of pivot element 400 according to one embodiment of the present invention.

Figure 5C Figure 5B is a bottom elevation view of pivot element 400 according to one embodiment of the present invention.

Figure 5D is a right side elevation view of pivot element 400 according to one embodiment of the present invention.

Figure 6 is a perspective view of the connection between the overhead support arm and pivot element of the triple axis coupling according to one embodiment of the present invention.

Figure 7A is a front elevation view of the first receptor coupling according to one embodiment of the present invention.

Figure 7B is a side elevation view of the first receptor coupling according to one embodiment of the present invention.

Figure 7C is a bottom elevation view of the first receptor coupling according to one embodiment of the present invention.

Figure 7D is a perspective view of the first receptor coupling according to one embodiment of the present invention.

Figure 8A is a perspective view of the tension bar according to one embodiment of the present invention Figure 8B is a front elevation view of the tension bar according to one embodiment of the present invention Figure 8C is a side elevation view of the tension bar according to one embodiment of the present invention.

Figure 9A is a front elevation view of the second receptor coupling according to one embodiment of the invention.

Figure 9B is a side elevation view of the second receptor coupling according to one embodiment of the invention.

Figure 9C is a bottom elevation view of the second receptor coupling according to one embodiment of the invention.

Figure 9D is a perspective view of the second receptor coupling according to one embodiment of the invention.

Figure 10A is a perspective view of the motor torque housing according to one embodiment of the present invention.

Figure 10B is a front elevation view of the motor torque housing according to one embodiment of the present invention.

Figure 10C is a side elevation view of the motor torque housing according to one embodiment of the present invention.

Figure 10D is a bottom elevation view of the motor torque housing according to one embodiment of the present invention.

Figure 11 is a diagramatic representation illustrating the swing directions allowed by the three independent axis according to one embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION Figures 1 and 2 illustrate the wrap brush assembly, in side elevation and top view respectively, for cleaning the outer surface of a vehicle according to one embodiment of the invention. In the embodiment shown, the wrap brush assembly includes a support structure 100 comprising two pairs of standards 105, each pair located on opposing sides of the path 140 traversed by a vehicle to be cleaned. Cross braces 106 rigidly connect each standard 105 forming the pair, and provide a mounting surface for one or more bridge members 115. The bridge members 115 are rigidly attached to cross braces 106 as shown, and extend between the pairs of standards 105 to form an upper support structure spanning over the path 140 traversed by a

vehicle to be cleaned. Stabilizer members 110 are rigidly attached to the lower end of standards 105 to provide a stable platform for the wrap brush assembly. The standards 105, cross braces 106, bridge members 115 and stabilizer members 110 are constructed of rigid square tube stock and plate material, and the rigid connections between these members may be by any type of permanent or semi-permanent connection, such as through bolting or welding.

A pair of overhead support arms 120,121 constructed of rigid square tube stock are pivotally connected to bridge members 115 such that the overhead support arms 120,121 are capable of pivoting through a substantially flat arc to allow the wrap brushes 135 to move from side to side, relative to the direction of vehicle travel 140 through the washing apparatus. This side to side movement allows the wrap brush 135 to move across the front, side, and rear surfaces of the vehicle as the vehicle is moved past the wrap brushes assembly.

Figure 3 is a perspective view of a typical connection between the overhead support arms 120,121 and the bridge members 115 according to one embodiment of the present invention.

In the embodiment illustrated, an arm support plate 320 is suitably fixed to the bridge members 115 as shown. The connected may be by mechanical means, such as through bolting or other permanent or semi-permanent methods, such as by welding. Pivot bearings 305 are semi-permanently fixed to support plate 320 by, for example, through bolting, and oriented to accept pivot pin 300. In a preferred embodiment, the pivot bearings 305 are pillow block type bearings.

The overhead support arm 120 is pivotally connected to an arm support plate 320 by a pivot pin 300 received within pivot bearings 305. In a preferred embodiment, pivot pin 300 is

vertically oriented to allow the overhead support arm 120,121 to swing in a substantially flat arc.

Figure 3 also shows support arm stops 310 and retraction arms 315. Support arm stops 310 are adjustable stops fabricated from plate steel and high durometer rubber that limit the swinging motion of the overhead support arms 120,121. This constraint may be necessary to prevent the wrap brush assembly from causing damage to other equipment or vehicles being washed.

As the overhead support arms 120,121 approach the outer limits of the desired range of swing, the rubber stops at the ends of the support arm stops 310 contact the side surface of the bridge members 115, stopping the swinging motion.

The retraction arms 315 may be passive hydraulic or pneumatic cylinder members and provide dampening and shock absorption for the swinging movement of the overhead support arms 120,121. In a preferred embodiment of the invention, the retraction arms 315 are active hydraulic or pneumatic cylinder members that allow the swinging movement of the overhead support arms 120,121 to be manually or automatically controlled. For example, if the desired wash cycle does not include washing the vehicle with the wrap brush assembly, the retraction arms 315 may be activated to swing the wrap brushes 135 out of position.

Turning again to Figures 1 and 2, the wrap brushes 135 are connected to the overhead support arms 120,121 by triple axis couplings 125. Motors 130 are mechanically fastened to the lower portion of each triple axis couplings 125, and provide the rotational motion to spin the wrap brushes 135 when cleaning a vehicle. In one embodiment of the invention, the motors 130 are hydraulically driven motors, although any motor capable of spinning the wrap brushes 135 in a vehicle washing environment may be used.

A perspective view of the triple axis coupling 125 according to one embodiment of the invention is shown in Figure 4. As disclosed above, couplings 125 are used to suspend the wrap brushes 135 from the overhead support arms 120,121, and provides three independent axis or directions in which the wrap brush can move in relation to the path traversed by a vehicle being cleaned. The triple axis coupling 125 is comprised of several different components, including: a pivot element 400, a first receptor coupling 410, a tension bar 420, a second receptor coupling 430, and a motor torque housing 440.

The pivot element 400 provides the connection point between the overhead support arms 120,121 and the triple axis coupling 125. A perspective view of the pivot element 400 is shown in Figure 5A. Figures SB through 5D illustrate front, bottom and right side elevation views of the Pivot element 400.

The pivot element 400 is constructed of plate and tube stock welded together in the configuration shown in Figures 5A through 5D, and includes a connection for a tension arm (not shown) at point 500. Tubular element 505 of pivot element 400 is adapted to pivotally accept a pivot pin not shown. A bearing 506, internal to tubular element 505, provides a low friction bearing surface between the tubular element 505 and a pivot pin (not shown). In a preferred embodiment, the bearing 506 is a low friction strong elastic synthetic material such as nylon.

The lower end of pivot element 400 is comprised of cylindrical member 510. Cylindrical member 510 is permanently affixed to the lower surface of tubular element 505, and provides a connection point for first receptor coupling 410.

A perspective view of the connection between the overhead support arm 120 and pivot element 400 of the triple axis coupling 125 is shown in Figure 6. A pivot pin 605 is suitably fixed to the free end of the overhead support arm 120 as shown. This

attachment may be, for example by welding, threading or through bolting. The diameter of pivot pin 605 and bearing 506 are such that once in position, the pivot element 400 is free to rotate about pivot pin 605 with a reduced amount of frictional resistance.

The connection between the overhead support arm 120 and pivot element 400 allows the pivot element 400 to move in a direction forward and backward with relation to the longitudinal axis of the overhead support arm 120, and provides the first independent axis or direction in which the wrap brush can move in relation to the path traversed by a vehicle being cleaned.

The top end, point 500 of pivot element 500 is connected to tension arm 600 by a through bolt fastener. In one embodiment of the invention, the tension cylinder 600 is a passive hydraulic or pneumatic cylinder member and provides dampening and shock absorption for the swinging movement of the triple axis coupling 125 and wrap brush assembly 135. In another embodiment of the invention, the tension cylinder 600 is an active hydraulic or pneumatic cylinder members that allow the swinging movement of the triple axis coupling 125, and thus the wrap brush assembly 135 to be manually or automatically controlled. As described earlier, there may be instances where the desired wash cycle does not include washing the vehicle with the wrap brush assembly. In these instances, the tension cylinder 600 may be activated to tilt the wrap brushes 135 out of position.

The pivot element 400 is rigidly connected to the first receptor coupling 410. Front, side, bottom and perspective views of the first receptor coupling 410 according to one embodiment of the invention are shown in Figures 7A through 7D respectively.

The body of the first receptor coupling 410 includes two main components, a receptor housing 700 and receptor cover 705.

In a preferred embodiment, the receptor housing 700 is machined

from solid cylindrical stock to form a cavity 715 sized to receive the circular end of tension bar 420 (not shown). A slot 710 machined through the bottom surface of receptor housing 700 allows the cylindrical rod section of the tension bar 420 (not shown) to exit through the bottom surface of the receptor housing 700.

The receptor cover 705 is constructed of plate stock and machined to cover the receptor housing 700. When in place, the receptor cover 705 and receptor housing 700 form an enclosure with cavity 715. Apertures machined through receptor cover 705 and receptor housing 700 are concentrically aligned to allow the two components to be fastened together utilizing through bolts 710.

A socket pad (not shown) is inserted in the cavity 715 to provide a socket bearing surface for the ball end of tension bar 420 (not shown) The receptor cover 705 is rigidly fixed to the pivot element 400 through a permanent or semi-permanent means. In a preferred embodiment of the invention, the receptor cover 705 is welded to the lower end 510 of the pivot element 400 before being through bolted to the receptor housing 700. In this embodiment, the receptor cover 705 functions as a flange.

The triple axis coupling 125 also comprises a second receptor coupling 430. The second receptor coupling 430 is similar in construction to the first receptor coupling 410, but oriented in an inverted position when in use. Front, side, bottom and perspective views of the second receptor coupling 430 according to one embodiment of the invention are shown in Figures 9A through 9D respectively.

Like the first receptor coupling 410, the body of the second receptor coupling 430 includes two main components, a receptor

housing 900 and receptor cover 905. In a preferred embodiment, the receptor housing 900 is machined from solid cylindrical stock to form a cavity 915, sized to receive the circular end of tension bar 420 (not shown). A slot 910 machined through the top surface of receptor housing 900 allows the machined rod section of the tension bar 420 (not shown) to exit through the top surface of the receptor housing 900.

The receptor cover 905 is constructed of plate stock and machined to cover the receptor housing 900. When in place, the receptor cover 905 and receptor housing 900 form an enclosure with cavity 915. Apertures machined through receptor cover 905 and receptor housing 900 are concentrically aligned to allow the two components to be fastened together utilizing through bolts 910.

A socket pad (not shown) is inserted in the cavity 915 to provide a socket bearing surface for the ball end of tension bar 420 (not shown).

The tension bar 420 having a first and second end is pivotally connected to the first and second receptor couplings 410,420 respectively, through ball and socket joints. These two connections provide the second and third independent axis or directions in which the wrap brush can move in relation to the path traversed by a vehicle being cleaned. Perspective, front and side views of the tension bar 420 according to one embodiment of the invention are shown in Figures 8A through 8C.

The tension bar 420 is comprised of three main components: ball ends 800 and 820, and shaft 805. The ball ends 800,820 are sphere-like members machined from solid stock, each having a sphere-like end and a flat bottom. The ball ends 800,820 are rigidly attached to the shaft 805 by a semi-permanent means.

In a preferred embodiment, ball ends 800,820 are fixed to the shaft 805 by a screw fastener connection. To facilitate this connection, a cylindrical protrusion 830 is machined into each end of shaft 805. The end of each protrusion 830 is drilled and tapped along the shaft 805 longitudinal axis to accept a screw fastener. Each ball end 800,820 is through drilled along the diameter from a point oriented in the center of the flat end. A second cavity, concentrically oriented with the drilled hole, is machined to accept the protrusion 830 as shown. Once the ball ends 800,820 are place over the protrusion 830 in shaft 805, a screw fastener is threaded through ball ends 800,820 into protrusion 830 thus fixing ball end 800,820 to shaft 805.

The first and second ends of shaft 805 are machined flat to form shaft ends 810,815 respectively. The shaft ends 810,815 and slots 710,910 in the first and second receptor couplings 410,430 are sized to allow the shaft ends 810, 815 to pass through slots 710,910 respectively without interference, but prevent shaft ends 810,815 from significantly rotating with relation to first and second receptor couplings 410,430.

The flat surfaces of shaft ends 810, 815 are oriented in offset angular relation to each other. This orientation, and the inability of the shaft ends 810,815 to significantly rotate with relation to the first and second receptor couplings 410,430, maintains an offset angular relationship between each of the three independent axis of the triple axis coupling 125.

In a preferred embodiment the angle between the flat surfaces of shaft ends 810, 815 is 60 degrees. Consequently, the angle between the pivot axis provided by the first receptor coupling 410 and the second receptor coupling 430 will be 60 degrees.

The second receptor housing 430 is rigidly affixed to the motor torque housing 440. This connection may be by any permanent

or semi-permanent means. In a preferred embodiment, the rigid connection between the receptor housing 430 and motor torque housing 440 is accomplished by mechanical fasteners, such as through bolting.

Perspective, front, side and bottom views of the motor torque housing 440 are shown in Figures bA through 10D respectively. The motor torque housing 440 is constructed of plate and tube stock welded or mechanically fastened together in the configuration illustrated.

As disclosed above, the top end 1000 of the motor torque housing 440 is rigidly attached to the second receptor housing 430. Apertures 1005 are machined through the top end of motor torque housing 440 and receptor cover 905 and are concentrically aligned to allow the two components to be fastened together utilizing through bolts 910.

Motor haunches 1010 are rigidly affixed to the sides 1015 of the motor torque housing 440 to provide a support for the motor mounting plate (not shown). A brush mounting member is comprised of square tube 1020 and plate 1025 rigidly affixed together. The brush mounting member is rigidly connected to the lower surface 1030 of the motor torque housing 400, and oriented such that an aperture 1035 in plate 1025 allows the wrap brush shaft (not shown) to pass through and couple with the motor shaft (not shown) for the motor (not shown) mounted inside the motor torque housing 400.

Figure 11 is a diagramatic representation illustrating the swing directions allowed by the three independent axis according to one embodiment of the present invention.

Swing direction 1100 describes the movement allowed by axis 1, i. e. the movement of the pivot element 400 in relation to the overhead support arm 120. As described earlier, this movement is

in a direction forward and backward with relation to the longitudinal axis of overhead support arm 120.

Similarly, axis allows the movement, swing direction 1105, of the first ends of the tension bar 420 in relation to the first receptor coupling 410, and thus the pivot element 400. Axis 3 allows the movement, swing direction 1110, of the second receptor coupling 430, and thus the motor torque housing 440 and wrap brush 135, with relation to the second end of the tension bar 420. One of ordinary skill in the art would understand that these movements (1100,1105 and 1110) are substantially normal to the longitudinal axis 1,2 and 3 respectively and provide some amount of movement in all four quadrants of a two dimensional coordinate system.

The net movement of the wrap brushes 135 with relation to the path traversed by the vehicle being cleaned is a function of the individual movements 1100,1105, and 1110 allowed by the three independent axis. The three individual movements can be reduced to component movements in a standard coordinate system, such as a standard two or three dimensional Cartesian coordinate system. In such instances, the net movement of the wrap brush 135 can be described as the summation of the individual component movements of each element in the triple axis coupling 125 along each coordinate axis in the coordinate system.

To facilitate the movement of the wrap brushes 135, the second and third axis, and thus swing directions 1105 and 1110 are angularly offset from swing direction 1100, in opposite directions as shown in Figure 11. The angles chosen for the offsets are directly related to the configuration of the vehicle washing apparatus, particularly, the position of the pivot point (created by pivot pin 300) of the overhead support arm 120 on the bridge members 115. In a preferred embodiment of the invention, the angles of the offsets are sufficient to accommodate various

width vehicles being cleaned by the wrap brush assembly as described below.

Since all vehicles are not of uniform width, the geometry of the wrap brush assembly may change for each different size vehicle being cleaned. In particular, the angular relationship between the overhead support brackets 120,121 and the bridge members 115 may change as wider or narrower vehicles pass the wrap brushes 135.

Referring again to Figure 2, as an average size vehicle 210 being cleaned passes through the standards 105, the wrap brushes 135 contact the front of the vehicle 210. The wrap brushes 135 are then pushed around the sides of the vehicle to a position shown typically in Figure 2, creating angles 200,220 between the upper support arms 120,121 and reference lines 225,230 perpendicular to the bridge members 115. It would be apparent to one of skill in the art that wider cars would produce greater angles 200,220, while narrower cars would result in smaller, or sometimes negative angles 200,220.

As disclosed earlier, the net free movement of the wrap brushes 135 with relation to the path traversed by the vehicle being cleaned is a function of the individual movements 1100, 1105, and 1110 allowed by the three axis. The net free movement is also a function of the angles 200,220, since these angles determine the position of the overhead support arm 120,121, and thus the swing direction 1100 for the first axis.

It is desirable to maintain net free movements of the wrap brushes 135 as close to the forward/backward and side-to-side directions, with relation to the path traversed by the vehicle being cleaned. Substantial movement in these directions will achieve sufficient cleaning of the vehicle 210, and minimize the forces exerted by the wrap brushes 135 on the sides of the vehicle..

As a vehicle being cleaned moves through the wrap brush apparatus, the first axis allows the pivot element 400 to swing in forward/backward directions 1100, at angles related to the wrap brush apparatus geometry, i. e. angles 200,220. Depending on the size and direction of the angles 200,220, the second and third axis, individually or in combination compensate for the angular forward/backward movement, and allows the wrap brushes 135 to have a net movement more closely aligned with the path traversed by the vehicle 210 being cleaned. In addition, the second and third axis individually or in combination, provide significant side-to-side movement of the wrap brush, in relation to the path traversed by the vehicle 210 being cleaned.

In one embodiment of the invention, the geometric configuration of the wrap brush apparatus is such that various size vehicles displace the overhead support arms 120,121 in such a manner as to create the following angles 200,220 : VEHICLE SIZE ANGULAR RANGE (degrees) Average-15 to 15 Large 15 to 30 Small-15 to-30 By way of example, a large vehicle 210 displaces the overhead support arms 120,121 creating angles 200,220 of 30 degrees as shown in Figure 2. Using the geometry described above, the first axis of the triple axis coupling 125 provides movement of the pivot element 400 in a direction approximately 30 degrees from the path traveled by the vehicle 210 being cleaned, i. e. direction 1100. The second axis allows the first receptor coupling 410 to move in a direction 60 degrees offset from the direction of the pivot element 400, as shown by swing direction 1105 in Figure 11. The net result of these two movements allows the wrap brushes 135 to move in a direction substantially

forward/backward and side-to-side with relation to the path traveled by the vehicle 210 being cleaned.

Similarly, a very small vehicle 210 displaces the overhead support arms 120,121 creating angles 200,220 of-30 degrees as shown in Figure 2. The first axis of the triple axis coupling 125 provides movement of the pivot element 400 in a direction approximately-30 degrees from the path traveled by the vehicle 210 being cleaned, i. e. direction 1100. The third axis allows the second receptor coupling 430 to move in a direction 60 degrees offset from the direction of the pivot element 400, as shown by swing 1110 in Figure 11. The net result of these two movements allows the wrap brushes 135 to move in a direction substantially forward/backward and side-to-side with relation to the path traveled by the vehicle 210 being cleaned.

For average sized vehicles that fall somewhere in between, i. e. when the angles 200,220 are between +/-15 degrees, the first, second and third axis compensate for the position of the overhead support arms 120,121. As illustrated in Figure 11, the first, second and third axis are oriented 60 degrees apart, and allow movement in both a positive and negative directions. As such, motion of the wrap brush in a direction other than directly along the swing directions 1100,1105 and 1110 is achieved by the aggregate motions allowed by the first, second and third axis.

For example, when the angles 200,220 are less than +/-30 degrees, the second axis over-corrects for the pivot element 400 movement (swing movement 1100) in swing direction 1105. The third axis compensates for this over-correction by allowing movement 1110 of the second receptor coupling 430, and thus the motor torque housing 440 in a direction geometrically offset from swing direction 1105. The result of the over-correction and compensation is a net free movement of the wrap brushes 135 that is more closely aligned to the path traveled by the vehicle 210 being cleaned than any single or dual axis alone.

It will be immediately apparent to those skilled in the art that variations and modifications to the disclosed embodiment are possible without departing from the spirit and scope of the present invention. The invention is defined by the appended claims.