Self contained high pressure hot water cleaning system for grocery carts

A self contained high pressure hot water cleaning system for grocery carts is disclosed in which a trailer mounted fully enclosed system allows the automatic passage of individual grocery carts from one end to the other by the use of a conveyor passing through a wash tunnel having spray nozzles. The wash tunnel also provides a pair of rotating brushes, a spent fluid holding tank, a cleaning fluid supply tank, a sanitizing fluid supply tank, associated pumps as well as a heater for heating the cleaning fluid. The self contained system further provides a hand operated wand at the entrance of the wash tunnel to allow an operator to remove difficult accumulation of grime from the grocery carts. A lifting table and exit ramp is also provided.

BACKGROUND OF THE INVENTION 
1. Field of the invention 
The invention relates to a self contained high pressure hot water cleaning 
system for grocery carts and in particular to such a system which is 
mobile and provides for the use of a sanitizing fluid application after 
cleaning. 
2. Discussion of the Technical Problems 
Supermarkets, grocery stores and the like provide grocery carts for 
customer's convenience. The carts are adapted to hold the customer's 
selected purchases. The carts thus contain food, including liquids, which 
in time are spilled or come in contact with the cart surfaces. Also many 
customers have small children who are carried in the carts. Not only is it 
unsanitary to continue to use dirty, unwashed carts but in time such use 
could promote the spreading of disease as microorganisms will multiply 
where food items have been left. 
Since it is good sanitation practice to have the carts cleaned at regular 
periodic intervals, a definate need exists for a system which will clean 
ordinary grocery carts in a short period of time. 
The standard wire rod or mesh basket grocery cart is provided with a 
handle, a basket mounted in a frame, and generally four caster mounted 
wheels. The carts vary greatly in design, however, they all present a 
basket to allow the purchaser to move their selected items and in most 
cases they provide a seat and pivoting support for the seat for the 
carrying of infants and small children. 
As previously mentioned, due to the nature of the produce hauled in the 
carts and the gradual accumulation of filth upon the carts it is highly 
desirable that the carts be periodically cleaned. Failure to thoroughly 
clean such carts could reduce the level of customers to a particular store 
since customers prefer not to use unsanitary, soiled carts. On the other 
hand, if the grocery carts were periodically cleaned and sanitized the 
food outlet store could advertise such a fact which would greatly enhance 
the trade at that outlet. 
The standard practice at most stores which utilize shopping carts is to 
clean the carts manually by the use of high pressure steam or hot water 
wands and then to have the detergent and hot water rinsed away by the use 
of a fresh water spray. 
Unfortunately, manual washing of carts is inefficient so that it costs far 
too much per cart to clean the carts. It also leaves a mess in the parking 
lot. It is not uncommon for large supermarkets to have 200 or more carts 
in their establishment, so inefficient manual washing of so many carts is 
too costly. The grocery store owner may be forced to increase the interval 
between washing cycles and thus deprive his customers of the clean, 
sanitary carts which they desire. 
In order to provide for an automatic cart washing system some inventions 
have been made which somewhat automate the process thereby eliminating the 
need for a total manual washing. Automation reduces the cost of washing 
the cart, however, the prior art cleaning devices for grocery carts suffer 
from a number of definate drawbacks. 
Prior art cleaning devices for grocery carts are generally of the type 
which provide an enclosure, spray nozzles, and a means for introducing the 
carts in a nesting fashion and retrieving them upon having the cart 
sprayed with a detergent solution. Such devices do not provide for a 
readily mobile washing of carts nor a complete system in which the carts 
are sanitized and ready for customers use. Also, such devices generally 
fail to provide for the recirculation of fluids employed so the fluids are 
wasted whereas they could be recycled to more efficiently wash the carts. 
Most of the grocery cart washing devices provide for a semi-automatic 
washing of the cart, however, none are known which provide for a mobile 
washing system utilizing high pressure hot water and using recirculating 
high pressure hot water, and sanitizing for the carts. Examples of known 
grocery cart cleaning devices can be found in U.S. Pat. No. 2,997,048 to 
Gertken, et al. issued Aug. 22, 1961, U.S. Pat. No. 3,179,117 to Gibson, 
et al. issued Apr. 20, 1965, and U.S. Pat. No. 3,698,029 to Pulliam issued 
Oct. 17, 1972. 
Very few devices in the known art relate to the automatic washing of 
individual grocery carts and none known are directed to provide such an 
automated washing system in which sanitizing is also provided for in the 
washing of the carts. 
In a different type of apparatus as disclosed in U.S. Pat. No. 3,736,948 to 
Crosswhite issued June 5, 1973, an apparatus for washing hospital carts is 
disclosed in which a sanitizing fluid from a remote source is used to 
spray upon hospital carts. 
U.S. Pat. No. 4,279,263 to Pulliam issued July 22, 1981, discloses a 
portable expandable structure for manually washing carts which includes a 
type of recirculating pump system. 
Although the prior art dicloses a number of interesting cart washing 
inventions, a complete cleaning and sanitizing system employing 
recirculating high pressure water and recirculating sanitizing fluid in a 
mobile self contained system adapted for a truck or trailer is not shown. 
Such an invention would greatly reduce the costs of washing grocery carts, 
thus allowing the store owners to have the carts washed and sanitized at a 
more frequent interval. 
Accordingly, a need exists for a self contained high pressure hot water 
cleaning system for grocery carts employing sanitizing fluid and being 
adapted for carriage on a truck or trailer so that it can be taken to a 
number of establishments for the cleaning of the grocery carts. Such a 
system would provide a simple, inexpensive apparatus that could wash a 
cart in a matter of seconds, return the cart to service with complete 
confidence of customers in its cleanliness. A cleaning system of that type 
would provide a system that is simple in design, easy to maintain, and 
easy to adjust to different types of grocery carts. Such a device should 
be easily repaired, not subject to damage by proper use and simple to 
manufacture. The instant invention is directed to all of these needs as 
well as to others as explained in the following summary. 
SUMMARY OF THE INVENTION 
The primary purpose of the invention is to provide a self contained high 
pressure cleaning system for grocery carts which is mobile, easily adapted 
to a number of designs of grocery carts, and provides for a self contained 
recirculation of fluids used so that when the operator has finished 
washing the carts no evidence of detergent, sanitizing fluid, grit, grime, 
or other debris is left as residue. The device is self-contained in that a 
grocery cart can be moved through the washing and sanitizing tunnel of the 
device and exited in a complete sanitized state without the necessity for 
employing additional stations or process steps. 
The purposes and features of the invention are obtained by providing a 
wheeled support frame having a floor containing a holding tank which is in 
fluid communication with drains. The frame is further provided with a 
washing tunnel situated on top of a holding tank. The tunnel provides a 
water containment enclosure for the spraying of high pressure hot water to 
dislodge grime and dirt from the grocery carts. The grocery carts move 
through the tunnel by the use of a conveyor. The water which is sprayed by 
nozzles in the tunnel onto the carts is recirculated by first draining 
through into the holding tanks where then it can be pumped for further use 
or it can be held if it becomes sufficiently dirty to be of no further 
use. The same tunnel apparatus is provided for a sanitizing fluid so that 
prior to exiting the cleaning system, the grocery cart would be sprayed 
with a sanitizing fluid to eliminate bacterial growth and insure 
customer's confidence in the cleanliness of the carts. 
The wheeled frame is also provided with a tank to hold a cleaning fluid 
such as a detergent and associated pump and heater to heat the cleaning 
fluid solution and heat it for better dislodging of dirt and grime. 
Nozzles are provided mounted at certain angles within the tunnel to spray 
the cleaning fluid as well as the sanitizing fluid onto the carts as they 
individually pass by. The carts are conveyed through the grocery cart 
cleaning system by the use of a belt conveyor which will easily accomodate 
any design of cart or any article for cleaning and sanitizing. Powered 
rotary brushes are provided in the walls of the cleaning tunnel to further 
scrape and remove excess dirt and grime buildup in the washing process. An 
area is provided upon the flat surface of the floor of the wheel platform 
to allow an operator to manually direct a high pressure wand upon 
particularly excessive buildups of dirt and grime upon the grocery cart. 
That area is known as the prewash area. 
An inclined lift is provided for directing the carts into the washing 
tunnel so that the operator need not lift each cart for cleaning. An exit 
ramp is provided for moving the clean, sanitized carts back down to the 
ground or floor surface.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
The self contained high pressure hot water cleaning system for grocery 
carts of the instant invention is depicted generally in FIG. 1. As can be 
seen by reference to FIG. 1, the invention 10 provides a frame 11 having 
an outer enclosure 12 which is essentially a trailer body. The frame 11 
and outer enclosure 12 is further provided with wheels 13 of manner common 
to trailers. Outer enclosure 12 includes not only the upper surface 14 but 
also side surfaces 15, rear doors 16, and front doors 17. 
Continuing with reference to FIG. 1 it can be seen that the rear doors 16 
are in an open position and that a preliminary channel 18 is shown in 
which is sufficiently wide for grocery carts to move. The interior channel 
18 does not have a closed upper surface and serves as a prewash area in 
that the grocery cart 19 can be placed within the prewash area and an 
operator standing in the open space 21 can direct a wand (not shown) to 
grocery cart 19 in a manner so as to remove any excessive accumulation of 
grime prior to the introduction of the cart 19 through the self contained 
system. 
With reference to FIG. 2 where the wash tunnel 20 is shown in which the 
grocery cart 19 can be conveyed by the use of a floor mounted conveyor 22 
and associated driving gears 23. Floor mounted conveyor 22 is further 
provided with endless belt 24 in a manner well known in the art. Wash 
tunnel 20 is comprised of a molded channel 26 having upstanding walls 27 
and 28. Optional upper covering 29 is provided to eliminate the amount of 
water which escapes from wash tunnel 20. Frame 11 provides a trailer frame 
upon which is mounted holding tank 31 which is in fluid communication with 
drain 32 within wash tunnel 20 which allow water to be collected in 
holding tank 31. 
As can be seen from reference to FIG. 2 supply tanks 33 and 34 are provided 
to contain cleaning solution and sanitizing solutions respectively. Those 
tanks are in fluid communication with nozzles 36, 37, and 38. The cleaning 
solution as contained in tank 33 or the sanitizing solution as contained 
in tank 34 upon the grocery carts 19 moving through tunnel 20. The fluid 
then drains through drain 32 and to hold in tank 31 which can then be 
emptied at a later date. The fluid in holding tank 31 could also be 
recirculated by pumping the fluid in holding tank 31 to spray through 
nozzles 36, 37, and 38. In that manner the spent fluid could be recycled 
to provide even greater efficiency of use. 
With respect to FIG. 3 it can be seen that wash tunnel 20 is provided with 
the belt conveyor 22 which is an endless belt 24 and operating on rollers 
23 in a manner well known in the art. It can also be seen from reference 
to FIG. 3 that vertical scrub brush 39 is included within wall 28 of wash 
tunnel 20 to provide a cleaning scrub of the carts as they pass through 
the wash tunnel. With continuing reference to FIG. 3 it can be seen that 
sanitizing pump 41 and sanitizing tank 34 are also included within 
enclosure 12. Prewash area 21 is provided with a high pressure water wand 
(not shown) in which an operator can spray a cart as it is in the prewash 
area 21. 
As shown in FIGS. 1 and 2 cart 19 sets upon pivoting platform 42 which is 
raised and lowered by means of hydraulic power cylinder 43 to lift the 
carts individually from the ground or floor up to a position which is 
horizontal with the entrance of wash tunnel 20. A drying area 50 is 
provided at the exit end of the apparatus 10 in which heated air or other 
means of drying is provided so that the carts emerge from the apparatus in 
not only a sanitized but also a dryed condition as well. 
Turning now with reference to FIG. 4 where the floor plan is depicted. In 
FIG. 4 it can be seen that holding tank 31 is situated on top of frame 11 
and frame 11 is further provided with a floor 43 upon which the operator 
can move about on either side of wash tunnel 20. The carts 19 as depicted 
in FIG. 1 are placed upon pivotal lifting table 42 and then moved to 
prewash area 21 whereupon they are set upon conveyor 22 to start moving 
through wash tunnel 20. Rotary brushes 39 rotate to scrape off the excess 
grime and spray nozzles 36 and 37 spray hot high pressure cleaning fluid 
upon the cart. Once the cart has passed the cleaning area it is then 
sprayed with a sanitizing fluid through nozzles 44 and 46 and then exited 
by way of dryer area 50 and down ramp 52 to be returned to service. 
As shown in FIG. 4 supply tank 33 for holding cleaning solution and supply 
tank 34 for holding sanitizing solution are included within enclosure 12 
so that the entire unit is self contained. Although many capacities could 
be used for the supply tanks 33 and 34 it has been found that 
approximately 300 gallons of cleaning solution in tank 33 and 300 gallons 
of sanitizing fluid in tank 34 is sufficient to handle the normal needs of 
a grocery store having approximately 200 carts. 
Continuing with reference to FIG. 4 it can be seen that the pump 53 which 
provides pressure for the cleaning fluid for the both the prewash area as 
well as within the hot water high pressure washing area is located next to 
the dryer area 50 in the forward portion of the device 10. A heater space 
54 is also provided for heating the water as well as heating the air which 
is used in the drying portion 50. 
An electrical connection switch box as well as hydraulic controls are 
located in the control box 56 which is close to area 57 in which the 
operator stands in order to control the entire operation of the washing of 
the carts. 
Although specific applications, materials, components, sequences of events, 
and methods have been stated in the above description of the preferred 
embodiment of the invention, other suitable materials, other applications, 
components and process steps as listed herein may be used with 
satisfactory results and varying degrees of quality. In addition, it will 
be understood that various other changes in details, materials, steps, 
arrangements of parts and uses which have been herein described and 
illustrated in order to explain the nature of the invention will occur to 
and may be made by those skilled in the art, upon a reading of this 
disclosure, and such changes are intended to be included within the 
principles and scope of this invention as hereinafter claimed.