Patent application title: Trailer mounted portable lavatory
Jay P. Poust (Red Oak, IA, US)
IPC8 Class: AE03D100FI
Class name: Baths, closets, sinks, and spittoons flush closet with holding tank
Publication date: 2012-07-05
Patent application number: 20120167297
A towed trailer mounted portable sanitary facility for use in the field
by workmen that has a longer period between servicing due to large volume
on-board fresh water and waste collection tanks, respective pumps and
controls for operating the pumps associated with each of the tanks, and a
rechargeable battery system for controlling the pumps so that the trailer
can be maintained and operated for lengthy periods without the need for a
1. A mobile sanitary system comprising: a wheeled flatbed trailer
including means for connecting to a towing vehicle; at least one toilet
facility mounted to the flatbed trailer; a combined fresh water and waste
collection tank having separate portions for containing fresh water and
collected waste mounted laterally across the underside of the flatbed
trailer; on-board electrically operated pump means for transferring fresh
water from the fresh water portion of said tank to replenish the flush
capacity of the toilet facility; and, on-board circuit means including a
rechargeable battery for controlling the pump means and for controlling
the recharging of the battery.
2. The mobile sanitary system of claim 1 further comprising a bi-lateral stability means attached to the flatbed trailer for maintaining level operation of the toilet facility when in operation.
3. The mobile sanitary system of claim 1 further comprising a retractable stair access means located across the rear of the flatbed trailer.
4. The mobile sanitary system of claim 3, wherein the retractable stair access means includes at least one safety rail and a locking mechanism to retain the stair in a stowed position.
5. The mobile sanitary system of claim 1, wherein the on-board circuit means includes a multi-source electrical recharging circuit accommodating external 120 volt ac or 12 volt dc currents to recharge the on-board battery.
6. The mobile sanitary system of claim 1, wherein the on-board circuit means can be operated by connecting to an external 120 volt ac source converted to 12 volts dc, a 12 volt dc vehicle output, and a generator producing either 120 volts ac converted to 12 volts dc or 12 volts dc.
7. The mobile sanitary system of claim 1 further comprising a fresh water reservoir for hand washing within the toilet facility that is capable of replenishment from the on-board pump means.
8. The mobile sanitary system of claim 1, wherein the on-board pump means includes an individual fluid pump for each combined fresh water waste collection tank mounted to the flatbed trailer.
BACKGROUND OF THE INVENTION
 This invention relates to a self-contained portable lavatory which has separate tanks, a fresh water storage tank and waste collection tank, contained within and beneath the wheeled relocatable unit. The portable lavatory is mounted onto the upper portion of a flatbed trailer and the waste collection and fresh water storage tanks are mounted onto the under portion of the flatbed trailer. The fresh water tank is used for storing fresh water until needed to flush and clean the sanitary facility and then re-supplying fresh water to the portable lavatory utilizing an on-board rechargeable power source for controlling the flushing and re-supply.
 Portable lavatories are well known. These devices are capable of being set up and maintained in a variety of outdoor locations, including sporting events, construction sites, concert arenas, and the like. Transportation is frequently achieved by flatbed trucks, which may include hydraulic or electrical lifts to move the toilets between locations.
 Many existing portable lavatories require routine maintenance to remove waste material, clean the internal components, and add fresh water to toilets. A separate vehicle is used to maintain and replenish the portable toilets. These vehicles usually have self-contained waste storage tanks with a vacuum pump system for collecting the waste from the portable lavatories, as well as a clean water tank for replenishing the flush tanks of the sanitary facilities. They typically have separate storage containers for waste and clean water and the containers range in size to correspond to the service area requirement. Such existing portable lavatories include those described in U.S. Pat. No. 4,653,125 [Porter] which discloses a portable sanitary facility which has a multitude of toilets or urinals on a trailer adapted for coupling to a towing vehicle having a tank to collect waste having an outlet for connecting to a separate vacuum/pump system when the waste tank becomes filled. Similarly, the system of U.S. Pat. No. 3,992,727 [Elkins] may be described as a portable urinal mounted onto a base with a pair of wheels with a hitch and a receptacle to receive liquid waste. Neither of the devices of Porter or Elkins is capable of flushing with the liquid waste collected by gravity feed into a tank below, nor do they describe an onboard clean water tank. The devices simply maintain only liquid waste collecting tanks.
 Many existing portable lavatories have a toilet and sink combination with a waste collection and fresh water tank located within the lavatory itself so that the amount of clean water that can be held in the tank is small because it is contained within the portable toilet/sink unit. For example, U.S. Pat. No. 7,137,156 [Yang] discloses a portable lavatory which is loaded onto a flatbed truck and contains a fresh water tank and foul water tank within the lavatory unit with a toilet and washbowl within each lavatory unit. The Yang apparatus goes to great length to describe the alterability of the fresh and foul water tanks in inverse proportion to each other, with a third variable tank between the two. The system described is much more complex that the present invention, requiring a special flange arrangement for correct operation of the clean and waste water tanks. Additionally, U.S. Pat. No. 5,548,856 [Julian] discloses a mobile sanitation station with a toilet and hand washing system on a flatbed trailer with holding tanks located behind each unit located above the trailer bed. The system of Julian provides fresh water to the hand washing station alone, with waste water from the washing bowl comingled with the waste water from the sanitary facilities. The Julian system does not address any onboard tank to be used for cleaning and replenishing both the hand washing and sanitary facilities without the need for external maintenance of the facilities.
 Existing flushable units have been altered to include water retention tanks for use in carrying additional flushing fluids. For example, U.S. Pat. No. 6,327,719 [Lobertmann, et al.] discloses a portable restroom with a base assembly located below the sanitary facility that includes an internal tank capable of maintaining and carrying flushing fluid. Lobertmann does not disclose use of the portable restroom with a hand washing station or any additional tank systems for carrying clean water for use in the sanitary facility that would lengthen the time between required maintenance of the sanitary facility.
 Many existing portable lavatories are for use in campers and have a combination of toilet, sink and shower facilities all located within the upper portion of the camper trailer. For example, U.S. Pat. No. 4,454,613 [Palmer] discloses a compact towable camper facility having a sink, shower and toilet system on a towable frame with an electrical and/or gas water heater for hot or cold water being available. The apparatus that is included in the towable camper trailer requires continued periodic maintenance of both its fresh and waste water tanks, in accordance with their respective sizes, at sanitary camper facilities usually maintained at camping sites.
 Finally, U.S. Pat. No. 6,723,173 [Golladay] discloses a payload transporter, i.e., a flatbed truck body, with a tank located on the bottom portion having a wall separating fresh water from waste water. The payload transporter is capable of carrying a portable toilet facility and contains a vacuum system to remove waste from the portable toilet. The Golladay apparatus describes a modification to include a fresh water tank to clean and replenish the sanitary facility, but there is no description included explaining how these actions are to be conducted or how the clean water is to be routed from the tank bottom port to the sanitary facility holding tank. The onboard pump is described as being used solely in conjunction with the vacuum emptying of the waste from the sanitary facility into the waste holding tank. It is apparent that short term periodic maintenance is still required for the Golladay system.
 None of the existing systems contain a separate fresh water and a waste collecting tank which are large in size and attached to the under portion of a flatbed connected to a toilet located above which is capable of being flushed and replenished from the fresh water tank. Additionally, the present invention contains a dump valve to facilitate easy removal of waste while the portable unit remains on site and in service.
 It is, therefore, an object of the present invention to provide a portable sanitary facility that can be self-sustaining for lengthier periods of time without the short-term need for routine maintenance by dumping the waste tank through vacuum pumping and replenishing a clean water tank to maintain the sanitary facilities for longer interim periods by using an on-board rechargeable power source to operate the several pumps to flush and re-fill the sanitary facilities for full operability. It is also an object of the present invention to permit the portable sanitary facility to be relocated without the requirement of interim maintenance prior to relocation of the sanitary facility.
 It is a further object of the present invention to provide onboard storage of a sufficient amount of clean water to be used for hand washing, cleaning sanitary facilities, and replenishing flush capacity for the sanitary facilities without the short-term need for on-site maintenance servicing of the clean and waste water tanks. It is still a further object of the present invention to provide an easily towable portable sanitary facility trailer system for one or more sanitary facilities that can be transported by any vehicle with a comparable towing hitch, obviating the need for a special vehicle to relocate the portable facility.
 It is yet another object of the present invention to permit either direct power operation of the on-board pump to facilitate the flushing and re-filling of the sanitary facilities, or operate the pump using the on-board rechargeable power source. In this manner, external maintenance is not going to be needed as often since the pump is fully operable from the on-board rechargeable power source, or by being connected to a vehicle 12 volt output, converted 120 volt ac power source, or generator as the source of the dc power to operate the pump facilitating the flushing and re-filling of the sanitary facilities.
 Other objects will appear hereinafter.
SUMMARY OF THE INVENTION
 The present invention is a mobile or self-portable sanitary system mounted onto a wheeled flatbed trailer that has a hitch for connecting to another vehicle for towing from any location to a worksite, or from worksite to worksite, or from one location within a worksite to another. The sanitary system includes at least one toilet facility mounted to the flatbed trailer with a combined fresh water and waste collection tank, having separate portions for containing fresh water and collected waste, mounted laterally across the underside of the flatbed trailer. The sanitary system also includes an on-board electrically operated pump for transferring fresh water from the fresh water portion of the combined tank to replenish the flush capacity of the toilet facility and on-board circuitry, including a rechargeable battery, for controlling the pump means and for controlling the recharging of the battery.
 When the mobile sanitary system is to be used by positioning the system at a worksite, a set of bi-lateral stability jacks or legs are deployed. These adjustable legs are attached to the flatbed trailer along the rear sides behind the wheeled axle and are utilized for maintaining level operation of the toilet facility when in operation. In order to gain easy access to the trailer mounted toilet facility the mobile sanitary system includes a retractable stair located across the rear of the flatbed trailer. The retractable stair includes at least one safety rail and a locking mechanism to retain the stair in a stowed position.
 The mobile sanitary system has a self-contained electrical switch and control circuitry including a multi-source electrical recharging circuit accommodating external 120 volt ac or 12 volt dc currents to recharge the on-board battery and to control the pump or pumps for providing fresh water for toilet flush replenishment or for cleaning purposes through a retractable hose line and valve. Alternatively, the sanitary system may be operated by being connected to a vehicle 12 volt output, a converted 120 volt ac power source, or a generator as the source of the dc power to operate the pump facilitating the flushing and re-filling of the sanitary facilities.
 The mobile sanitary system may also include a fresh water reservoir for hand washing within the toilet facility that is also capable of replenishment from the on-board pump means. The mobile sanitary system can accommodate additional on-board pumps with an individual fluid pump for each combined fresh water waste collection tank mounted to the flatbed trailer. In this manner, the time between required maintenance service is extended and there is no need for a portable toilet company to come to a worksite to relocate a portable toilet, or for that company to pick-up the portable toilet and transport it to a different worksite.
BRIEF DESCRIPTION OF THE DRAWINGS
 For the purpose of illustrating the invention, there is shown in the drawings forms which are presently preferred; it being understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown.
 FIG. 1 is a left side view of the portable sanitary facility system of the present invention.
 FIG. 1A is an enlarged section of the front portion of the trailer frame, bed and undercarriage showing the onboard pump and tank system of the present invention.
 FIG. 2 is a right side view of the portable sanitary facility system of the present invention.
 FIG. 3 is a rear view of a single sanitary facility mounted atop a towed vehicle platform of the present invention.
 FIG. 4 is a rear view of a dual sanitary facility mounted atop a towed vehicle platform of the present invention.
 FIG. 5 is a diagram of the rechargeable battery and control switch circuitry for the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
 The following detailed description is of the best presently contemplated mode of carrying out the invention. The description is not intended in a limiting sense, and is made solely for the purpose of illustrating the general principles of the invention. The various features and advantages of the present invention may be more readily understood with reference to the following detailed description taken in conjunction with the accompanying drawings.
 Referring now to the drawings in detail, where like numerals refer to like parts or elements, there is shown in FIG. 1 the portable sanitary facility 10 of the present invention. The portable sanitary facility is comprised of a single axle trailer, generally 12, onto which is mounted a sanitary facility, generally 32, both to be described in greater detail as follows.
 The trailer 12 is shown with a single axle having wheels 13, 14 on its left and right sides, respectively. When in the parked and supported mode, the trailer 12 is supported in the rear by the axle and wheels 13, 14 and the jack 16 that is manually operated by crank 15 to extend leg 17 to provide a substantially level platform for use of the sanitary facility 32. As shown in FIG. 2, the jack 16 and crank 15 are rotated to their storage positions along the trailer tongue 18. At the forward end of the tongue 18 are the ball hitch capture mechanism 20 that attaches to the vehicle towing hitch 19 with the towing ball 21 attached at its distal end, as shown in FIG. 2 with the securing nut extending downward from the hitch 19. FIG. 2 shows the portable sanitary facility 10 mounted to a vehicle hitch 19 ready to be transported from one location to another.
 Also providing stability to the trailer 12 are a pair of extension legs 27, 28 positioned at the rear left and right corners of the trailer bed. The extension leg 27 is shown in the extended or jacked position in FIG. 1 and the paired extension leg 28 is shown in the stowed position in FIG. 2. These legs 27, 28 provide lateral and longitudinal stability for the trailer bed creating a substantially level platform for the portable sanitary facility 32 when deployed.
 Referring now to both FIGS. 1 and 2, extending around the front and sides of the trailer bed are retention walls 21, 22 that are utilized to create a significant framework at the trailer bed to retain the portable sanitary facility in position on the trailer 12. In addition, the portable sanitary facility 32 is fastened to the trailer bed in any suitable manner so that the sanitary facility remains in one stationary position and does not slide forward or backward, or from side to side, when in transit. With the portable sanitary facility 32 mounted in a fixed position, the waste line from the facility 32 can be connected through the trailer bed to a combination fr4sh water waste collection tank 42 located across the bottom mid-section of the trailer 12. The waste collection portion of tank 42 receives the waste fluids, and any solids they may contain, from the sanitary facility 32 and holds the waste until full when external servicing will be required. To accommodate external servicing of the waste portion of tank 42, a waste tank connection valve 52 with removable cap 54 are positioned for ease of connection to an external waste collection unit (not shown) providing for the elimination of the waste fluids from the waste collection portion of the storage tank 42. A sight glass 56 is provided in the waste collection portion of the tank 42 for ease of determining the level of waste in the tank 42 in order to schedule servicing and removal of the collected waste. The combined fresh water and waste collection tank 42 is shown extending part way along the length of and laterally across and underneath the bed or platform of trailer 12, as shown in FIGS. 1, 2 and 3. The combined fresh water and waste collection tank 42 extends laterally across and underneath the platform of trailer 12 so as to provide a more uniform distribution of weight as the combined fresh water and waste collection tank 42 dispenses the fresh water and collects the combination liquid/solid waste from the sanitary facility 32.
 The portable sanitary facility 10 also includes a fresh or clean water portion of tank 42 that is filled from an external source through associated fill line 44. Atop the fill line 44 is a threaded cap 45 to close off the fill line 44 when not needed to replenish clean water for the tank 42. The clean water portion of tank 42 is connected to the onboard hose line 62 by connecting hose 46 that extends beneath the trailer platform. The other end of hose line 46 connects to the clean water pump 48, partially shown in FIG. 1 and with a better view in FIG. 2, that is used to pump, on demand, clean water from the clean water portion of tank 42 to clean the sanitary facility 32 and to replenish flush fluids for the sanitary facility 32 in order to continue operating between full service maintenance of the entire portable sanitary system 10. A water drain line and valve 43 are connected to the clean water portion of tank 42 to facilitate emptying and/or flushing of the tank 42 as may be required for proper operation. On the outward facing sidewall of tank 42, there is a view window 47 to show the fluid level of the fresh water portion of tank 42 without the need to open the fill line 44 to determine the depth of the water within the tank 42. Reference should be made to FIG. 1A for an enlarged view of the left side of the trailer 12 showing the clean water portion of tank 42 and its associated component parts as described above.
 The pump 48 used with the clean water portion of combined fresh water and waste collection tank 42 is powered by an onboard rechargeable battery system 60 that operates at 12 volts dc, as shown in FIG. 5. The rechargeable battery 60 provides 12 volts operating power to the clean water pump 48 on demand for water to be pumped from the clean water portion of tank 42 to the hose line 62. Likewise, the rechargeable battery 60 may provide power to another clean water pump 148 to provide on demand fresh water to be pumped from the clean water portion of a second combined fresh water and waste collection tank 142 to the hose line 62. The rechargeable battery 60 can be recharged simply by attaching the battery 60 to any 12 volt power supply including, but not limited to, a vehicle 12 volt battery output, or an external power source 66 that could be either a connection to 120 volts ac to or a generator providing either 120 volts ac or 12 volts dc power. The external power source 62 may be connected to the recharging unit at either the higher voltage connection (120 volts ac) or the lower voltage connection (12 volts dc) to provide the 12 volt recharging circuit 60 the necessary power to keep the on-board 12 volt rechargeable dc battery 64 fully charged. The recharging circuit 60 is configured to control the battery recharge either by trickle charging or by applying immediate power to operate the pumps 48, 148. The circuit 60 also includes switches for operating each of the pumps 48, 148 individually to pressurize the fresh water line to the on-board hose 62. The circuit 60 is preferably located at the front of the trailer 12 with its external connections and switches available for manual connection and use by workmen servicing the sanitary facilities. Suitable coverings are provided for the electrical connections and the switches so that they are protected from the external environment.
 The sanitary facility 32 can be any of a number of portable facilities contained within a closable structure with a door and providing a chemical flush toilet with or without a hand washing station. Such sanitary facilities 32 are available from a number of manufacturers and are adapted to dump the collected waste into the waste collection portion of tank 42 by means of a connecting conduit (not shown). The sanitary facility 32 is positioned to open its door 34 toward the rear of the trailer bed. At the rear of the trailer bed is a set of collapsible steps 70 having a sufficient number of treads 72 to extend from the level of the trailer bed to the ground. The stair treads 72 spans the distance between the side supports 74. In addition, there is a stair rail 76 along the right side of the stairs 70, as shown in FIGS. 1-4. The collapsible steps 70 rotatably collapse upward about a pair of cylindrical hinge pins 78 secured through the sidewalls of the trailer bed. On the bottom of the steps 70, at the required height for rear facing stop lamps and in accordance with SAE standards, a stop lamp 80 is mounted that is operable simultaneously with the stop lamp function of the paired taillights 82 on the rear wall of the trailer bed.
 Referring to FIG. 4, there is shown a plurality of sanitary facilities 32, 132 positioned side-by-side and oriented for rearward opening of their respective doors 34, 134. In this embodiment having a plurality of sanitary facilities 32, 132 the trailer 12 becomes wider to accommodate the additional width of the two sanitary facilities 32, 132 positioned side-by-side. The rear collapsible steps 70 are also wider extending across the width of the trailer 12, and an additional stair rail 176 is installed on the left side of the steps 70. The stair rail 76 is maintained in the collapsed position by stair rail retaining pin 77 mounted on bracket 79 attached to the frame of the trailer 12. See FIG. 2. The stair rail retaining pin 77 retains the upper support of the stair rail 76 within the bracket 79 until manually released to permit the steps 70 to be extended for access to the sanitary facility 32. When in the lowered position, the rear stairs 70 provide access to the one or more sanitary facilities 32, 132 by workmen at the work site where the trailer 12 is located.
 In the embodiment showing two sanitary facilities 32, 132 shown in FIG. 4, the combined fresh water and waste collection tanks 42, 142, respectively are mounted side-by-side beneath the respective sanitary facility 32, 132. Each tank 42, 142 is connected using either a single pump 48, or with individual pumps 48, 148. If only a single on-board electrical pump 48 is used, then each tank 42, 142 is attached to the pump 48 and a single connecting hose 46 provides the fluid conduit to the hose 62. If two pumps are utilized, then each pump 48, 148 provides its output to a manifold (not shown) that has its output connected to the fresh water hose line 46 that is connected and provides fresh water to the hose 62.
 In order to replenish or clean the sanitary facility 32, the fresh water pump 48 is turned on to pressurize the hose line 62. The hose is located, preferably, on the side of the trailer closest to the door latch 36 on the sanitary facility 32, or the door latch 136 on the sanitary facility 132. In this manner the hose 62 does not need to reach around or under the open door to enable a workman to enter, spray down the surfaces in the facility and recharge the liquid flush system with clean water. The hose 62 is mounted on a reel 63 and has a nozzle with valve 65 at its distal end to control and direct the flow of clean water from the fresh water tank 42. A hose line runs from the fresh water portion of tank 42 underneath the trailer bed and connects to the hub of reel 63 to charge the hose 62 for use by a workman in cleaning the one or more sanitary facilities 32, 132. When the workman is finished using the hose 62, it is returned to the reel 63 and the pump 48 is turned off using the pump switch on the recharging control switch unit 60. In this manner the portable trailer mounted lavatory or sanitary facility 32 can be stationed in the field for an extended length of time without the need for another vehicle to provide service to clean the one or more lavatories 32, to provide fresh water for the clean water portion of tank 42, or to collect waste from the collected waste portion of tank 42 on board the trailer 12.
 In operation, the mobile sanitary facility 10 is positioned for towing behind a towing vehicle. The fresh water portion of tank 42 is filled through the fill line 44 from a fresh water source and the cap 45 threaded into position closing the fill line 44 in preparation for travel. The waste collection portion of the tank 42 is checked for any contents, any remaining waste is pumped out and the waste portion of tank 42 is flushed through the valve 52 and cap 54 is replaced prior to travel. The portable sanitary facility 10 is towed to the location where it is needed and the trailer 12 is unhitched from the towing vehicle. The leg 17 of the jack 16 is extended using the crank 15 and the stabilizing legs 27, 28 are deployed in the manner shown in FIG. 1. The rechargeable battery 64 is tested for full charge and, if lacking a full charge, the battery 64 is recharged using an external power source by plugging into a 120 volt ac line or by connecting to a vehicle 12 volt dc line. When fully charged, the battery 64 is capable of operating the pump 48 to pump fresh water from the fresh water portion of tank 42 through the hose 46 connecting the fresh water reservoir to the hose 62. The hose 62, in turn, can be unwound and by entering one of the sanitary facilities 32 is used to replenish the flush liquid, the fresh water reservoir used for hand-washing, and/or to clean the facility as needed. All of the waste connection from a sanitary facility 32, whether the toilet or the wash basin, empty into the waste collection portion of the tank 42. The level of waste collected and the level of fresh water can be viewed through the respective view windows 47, 56 along the external sides of the respective tank portions. Fresh water can be added at any time through the fill line 44 and service for the removal of the waste is requested when the view window 56 shows the waste collection portion of the tank 42 requires emptying. If the portable sanitary facility 10 needs to be relocated on the work site, or relocated to a different work site, it needs only to be re-hitched to a towing vehicle and towed to the new location. There is no need to have the sanitary facility 32 picked up and loaded onto another vehicle for transport to the new location. With the on-board power system for pumping the fresh water to the sanitary facility 32 for replenishment of fresh water and flush reservoirs and with the portable sanitary facility 10 permanently mounted to a towable trailer 12, the need for short term maintenance and for requesting the relocating of the sanitary facility by an outside vendor is no longer necessary.
 The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof and, accordingly, the described embodiments are to be considered in all respects as being illustrative and not restrictive, with the scope of the invention being indicated by the appended claims, rather than the foregoing detailed description, as indicating the scope of the invention as well as all modifications which may fall within a range of equivalency which are also intended to be embraced therein.
Patent applications in class With holding tank
Patent applications in all subclasses With holding tank