Rotation brush mechanism with speed control governor

A washing apparatus includes a centrifugal brake mechanism that limits a rotating speed of a rotary head supporting a ring of bristles, and also includes a mechanism which brings vanes of the rotary head into alignment with a high pressure water jet when the bristles of the washing apparatus are pressed against a surface to be washed. The device prevents excessive amounts of water from being thrown outward by the rotating bristles, yet is small enough to allow scrubbing of hard-to-reach portions of, for example, a car surface.

BACKGROUND OF THE INVENTION 
The invention relates to inexpensive portable washing devices of the type 
having a handle connected to a water hose and having a ring of bristles 
mounted on a rotary head powered by turbine vanes, and more particularly 
to mechanisms which limit rotating speed of the ring of bristles to 
prevent water from being thrown rapidly outward and soaking the user. 
A variety of inexpensive car washing devices of the type connectable to an 
ordinary garden hose and providing a rotary head supporting scrubbing 
bristles and powered by a jet of water produced by pressurized water 
delivered by the hose are known. Such devices commonly include a reservoir 
for detergent. Some include a control valve disposed in the handle of the 
device. U.S. Pat. Nos. 4,207,640; 4,151,624; 4,290,160; 4,461,052 are 
exemplary of the state of the art for such cleaning devices. FIG. 1 herein 
shows a typical prior art device, in which a housing 1 includes a recess 
in which a rotary head with vanes for receiving a pressurized jet of water 
9 is mounted by means of a bearing 3 and supports a scrubbing bristle ring 
4. A garden hose is attached by means of a hose connector 10 at the end of 
a handle 7 which includes a water passage 8 that guides the pressurized 
water through an orifice to produce the jet of water 9 which impinges upon 
the vanes of the rotary head 2. This particular device includes a 
stationary ring of peripheral bristles 6 attached to the outer bottom 
surface of housing 1. Peripheral bristles 6 act as a skirt that mainly 
performs the function of preventing excessive outward spraying of water 
from rotary bristle ring 4 as it rotates at high speed and thereby 
prevents the user from being soaked as he or she attempts to use the 
device to wash a car. Other prior art devices include plastic skirts which 
perform the same function as peripheral bristles 6 to prevent the user 
from being sprayed with water. 
All of the comparable prior art devices suffer from the shortcoming that 
either they have a peripheral skirt or peripheral bristles which confine 
the amount of water that is thrown outward so that the user will not get 
soaked when using the device, in which case the overall size of the head 
is too large to allow effective scrubbing of portions of the surface of an 
automobile that are hard to reach, for example between the radio antenna 
and the adjacent surface metal, or elements of the automobile's grill, or 
portions of the surface near the bumpers, etc. 
Despite the large number of prior inexpensive washing devices of the type 
described above that are available or have been proposed, there remains an 
unmet need for an inexpensive, washing device that (1) provides enough 
power to rotary bristles to adequately scrub the surface of an automobile 
or other object, (2) does not spray excessive amounts of water on the user 
during use, especially when the bristles are temporarily lifted off the 
surface being washed (causing the bristles to rotate much faster and 
thereby throw more water outwardly), and (3) is small enough to allow the 
bristles to be easily pressed against hard-to-get-at surfaces of the 
automobile or other object so that the user does not need to use another 
implement, such as a rag, to wash such hard-to-get-at surfaces in a 
separate operation. 
SUMMARY OF THE INVENTION 
It is an object of the invention to provide an inexpensive portable washing 
device that is connectable to a garden hose and which eliminates the 
peripheral skirt of prior similar devices, and yet does not radially throw 
excessive amounts of water on the user. 
Briefly described, and in accordance with one embodiment thereof, the 
invention provides a portable, inexpensive washing apparatus that includes 
a centrifugal brake mechanism which acts as a governor to limit the rotary 
speed of a rotary head and a ring of scrubbing bristles attached thereto, 
in order to limit the amount of water which is sprayed outward by the 
bristles when they are lifted from the surface to be washed, and yet does 
not reduce the amount of power applied to the ring of bristles when they 
are pressed against the surface to be scrubbed. In the described 
embodiment of the invention, a pair of brake elements having surfaces 
which frictionally engage an inner cylindrical surface of a housing of the 
washing apparatus when the rotary bristle head reaches a certain rotary 
speed act to prevent further increases in the rotary speed thereof. When 
the rotary bristle head speed is reduced by pressing the bristles of the 
apparatus against the surface to be washed, full power is applied to the 
rotary head and ring of bristles thereon by virtue of a pressurized water 
jet striking vanes of the rotary head. In one described embodiment of the 
invention, the rotary head is mounted slidably on an axial pin about which 
the rotary head rotates and is urged downward by a bias spring moving the 
vanes of the rotary head out of alignment with the high pressure, 
fan-shaped water jet when the bristles are not being pressed against a 
surface to be washed. When the car washing apparatus is deployed so that 
its bristles are pressed against a surface to be washed, the rotary head 
slides upward along the axial pin all the way into the recess of the 
housing, bringing the vanes into alignment with the high pressure jet of 
water and thereby applying power to the rotary head to cause rotation of 
the bristles.

DESCRIPTION OF THE INVENTION 
Referring now to FIGS. 2-4 reference numeral 12 designates the housing of 
the rotary brush of the present invention. Housing 12 is attached to a 
handle 7, as in FIG. 1, through which a high speed stream of water is 
directed to an orifice 8 to produce a high speed jet of water 9 which 
impinges upon vanes 15 of a rotary bristle head 28. A peripheral ring of 
bristles 13 is attached to the bottom surface of rotary bristle head 28. 
Bristle head 28 rotates in the direction indicated by arrow 32 in FIG. 2. 
Bristle head 28 includes a pair of hollow spokes 14 each attached at its 
inner end to a hub 21 through which an axle pin 19 extends. Suitable 
bearings such as 29 can be provided either in the housing 12 and/or in the 
hub 21 to provide low friction rotation. 
In accordance with the present invention, a centrifugal brake speed 
governor mechanism is provided in which two brake shoes 24 are slidably 
disposed in recesses 46 (FIG. 2) in outer opposed portions of rotary 
bristle head 28, so that the brake shoes 24 can move outward in the 
directions indicated by arrows 33 when the rotation speed of bristle head 
28 rotates. 
Brake pads 26 are disposed on the outer surface of brake shoes 24, and, 
when the maximum permissible speed of bristle head 28 is achieved, they 
frictionally rub an inner surface 25 of housing 12, which acts as a brake 
drum surface, thereby preventing further increases in rotation speed. 
At low speeds, brake shoes 24 are pulled inward into the recesses 46 by a 
pair of opposed springs 18, which have their outer ends connected to loops 
22 attached to the hub 21 and are connected up to the outer ends of the 
brake shoes 24 by means of loops 30. Reference numeral 30 designates side 
walls of housing 12, the inner surfaces of which are the "brake drum" 
surfaces 25. 
Various techniques can be provided for adjusting the tension of springs 18 
so that the speed-governing function occurs at the desired rotation speed 
of bristle head 28, at which amounts of water thrown outwardly by bristles 
13 are not excessive, even when the bristles are lifted from the surface 
33 to be washed. FIG. 5 shows one tension adjusting mechanism in which an 
adjustment screw 34, accessible through a hole in the center of brake shoe 
26, adjusts the radial position of loop 30 to which the outer end of 
spring 18 is connected, thereby adjusting the spring tension and hence the 
limiting speed of rotary bristle head 28. Similar mechanisms, accessible 
from the bottom of the bristle head 28, for adjusting the tension of the 
springs 18 from their respective inner ends, could be easily provided by 
one skilled in the art. 
Ordinarily, the housing 12 and the rotary bristle head 28 would be made of 
plastic. The brake pads 26 could be composed of plastic that is integral 
with the brakeshoes 24. The metal components, such as the spring and the 
bearings, could be composed of suitable rust resistant metal, such as 
stainless steel. 
Referring now to FIGS. 6A and 6B, an alternate embodiment of the invention 
is shown, wherein the rotary bristle head 28 is mounted on an axle pin 19A 
having a lower rataining head 44. Bristle head 28 is rotatably supported 
on axle pin 19A so that bristle head 28 can freely slide vertically in the 
directions indicated by reference numeral 47. A compression coil spring 39 
is disposed about the upper portion of axle pin 19A, which is imbedded in 
a raised portion 38 of the upper surface of housing 12. The lower end of 
compression coil spring 39 abuts the upper surface of rotary head 28. The 
upper end of the coil spring 39 engages a low friction bearing 29 which 
allows spring 39 to rotate freely with rotary bristle head 28. When 
bristles 13 are not being pressed against a surface to be washed, bristle 
head 28 is in the configuration shown in FIG. 6A, being retained on axle 
pin 19A by head 44. Under these conditions, the vanes 15 of rotary bristle 
head 28 are positioned below the pressurized water jet 40 emerging from 
the nozzle at the inner end of handle 7, and do not cause much, if any, 
rotation of bristle head 28. However, when the user exerts a downward 
force on handle 7, pressing bristles 13 against the surface 33 to be 
washed, the bristle head 28 is pushed all the way upward into the recess 
48 of housing 12, sliding along axle pin 19A, compressing spring 39, and 
bringing the vanes 15 into alignment with the water jet 40, causing full 
power to be applied to the rotary bristle head 28. The water jet 40 can be 
fan-shaped, if an enlongated nozzle aperture is provided therefor, so that 
the application of power from water jet 40 to vanes 15 is gradually 
increased as the bristle head 28 is pushed further up into recess 48. 
If desired, the centrifugal brake governor mechanism of FIGS. 2-4 can be 
combined with the receding rotary head of FIGS. 6A and 6B, in which case 
the speed of the governing mechanism will perform the function of limiting 
rotary speed of the bristle head 28 under conditions in which the ring of 
bristles 13 are being pressed only lightly against the surface 33, with 
sufficient force to bring the vanes 15 into alignment with water jet 40, 
but not with enough force to reduce the rotary speed of the bristle head 
28 enough to prevent water from being centrifugally thrown outward by the 
rotating bristles 13 and thereby prevent the user from being soaked. 
In FIG. 7, handle 7 is shown with two bends 50 and 51 which result in the 
outer end of handle 7 being at an angle which is very convenient for use 
of the washing apparatus to wash a car. Reference numeral 52 designates a 
coupling which allows head 12 to be removed from handle 7. A number of 
different sized and/or different types of removable heads can be provided, 
and a shut-off valve 53 can be provided in handle 7 to allow the different 
sized heads to be easily interchanged during a particular washing 
operation. 
While the invention has been described with reference to a particular 
embodiment thereof, those skilled in the art will be able to make various 
modifications to the described embodiments of the invention without 
departing from the true spirit and scope thereof. It is intended that all 
devices which are equivalent to the embodiments of the invention shown in 
that they perform substantially the same function in substantially the 
same way to achieve substantially the same result are to be encompassed 
within the invention. For example, a variety of different equivalent 
centrifugal brake mechanisms could be provided by those skilled in the 
art. Conventional liquid detergent dispensers selectively actuatable by 
the user can be easily provided in the handle or in the housing, and 
therefore are not disclosed or described. Various planetary or other gear 
reduction means could be provided to translate rotation from a high speed 
impeller to a lower speed rotary bristle head. Other means for adjusting 
the tension in the springs could be provided by those skilled in the art.