Abstract:
A canister for use in a liquid disposal device featuring a lid removal bracket and a canister bracket. The canister includes a lid featuring a patient port, a vacuum port and a lip adapted to be engaged by the lid removal bracket of the liquid waste disposal device. The canister also includes a body including an open top surrounded by a circumferential rim that is engaged by the lid in a removable fashion. A tab is attached to an exterior surface of the body of the canister in a generally horizontal extending fashion and is sized and vertically spaced from the circumferential rim so as to engage the canister bracket of the liquid waste disposal device when the canister body is positioned therein and turned about a generally vertical axis.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a divisional application of U.S. patent application Ser. No. 09/870,215 filed May 30, 2001, now U.S. Pat. No. 6,588,436, which is a continuation-in-part of U.S. patent application Ser. No. 09/483,295 filed Jan. 14, 2000, and issued on Jul. 24, 2001, as U.S. Pat. No. 6,263,887. 
    
    
     BACKGROUND OF THE INVENTION 
     I. Field of the Invention 
     The present invention relates generally to liquid waste disposal and canister flushing, and in particular to the disposal of liquid medical waste from containers which are flushed and cleaned to permit reuse. 
     II. Description of the Related Art 
     Various forms of liquid waste are commonly encountered in a variety of different situations. For example, liquid medical wastes are commonly produced in surgery and other medical procedures. Such wastes can include blood and other body fluids of patients, and major surgery can produce a number of containers of such waste from a single patient. Liquid medical waste generates significant disposal problems due to its possible contamination with various infectious diseases, including AIDS, hepatitis, MRSA and tuberculosis. In an effort to combat the risks associated with handling such liquid medical wastes and to protect medical personnel from the spread of infectious diseases, disposal procedures have become increasingly complicated and expensive. 
     One type of disposal procedure for liquid medical wastes involves emptying the waste canisters from surgery into specially designed plumbing fixtures. However, this procedure can involve risks associated with splash back and aerosolization whereby medical personnel can be exposed to the waste and bacteria present therein. 
     Another type of procedure involves the centralized collection of the waste with specially designed equipment having a liquid waste reservoir that must periodically be dumped. Such equipment is generally relatively expensive and can add significantly to the cost of equipping a hospital operating room or other treatment facility. 
     Yet another method of disposing of liquid medical waste involves mixing it with a solidifying agent in the container. The medical waste in the container is then disposed of pursuant to regulations governing the disposal of bio-hazardous waste. The disadvantages with this disposal method include the cost of the canister, which becomes a single-use item, and the extra charges for disposing of bio-hazardous waste, which is sometimes referred to as “red bag” waste. 
     Liquid medical waste disposal procedures can come under rules and regulations imposed by various governmental and regulatory agencies, including the Occupational Safety and Health Administration (OSHA), the Food and Drug Administration (FDA), the Center for Disease Control (CDC) and the Department of Transportation (DOT). 
     Heretofore there has not been available a liquid medical waste disposal system and method with the advantages and features of the present invention. 
     SUMMARY OF THE INVENTION 
     A liquid waste disposal and canister flushing system for a canister having a press fit lid features a cabinet having an opening with a hinged lid. A sink is positioned within the cabinet and communicates with a drain. A mounting bracket is affixed to the cabinet and includes a motor, a shaft connected to a canister bracket, and a shaft connected to a lid removal bracket. A canister sealed with a press fit canister lid is positioned in the canister bracket. As the canister is secured to the canister bracket the lid is loosened and positioned on a lid removal bracket. The cabinet is then closed. The canister is automatically rotated by the canister bracket to an inverted position within the chamber so that the contents drain out of the canister. The canister lid is rotated, relative to the canister, by the lid removal bracket to a position displaced from the canister and released so that it falls into a disposal collection tray. A pressurized cleaning solution and water are activated and sprayed within the chamber so that the canister is flushed and its contents drain into the sink and down the drain. Once the canister is sanitized it may be removed from the system and reused. 
     OBJECTS AND ADVANTAGES OF THE INVENTION 
     The principal objects and advantages of the present invention include: providing a liquid waste disposal and canister flushing system; providing such a system which facilitates the relatively inexpensive disposal of medical waste; providing such a system which permits safe reuse of medical waste containers; providing such a system which is relatively easily adapted for use with existing medical waste containers; providing such a system which reduces the splashing of medical waste being disposed; providing such a system which can reduce the hazards associated with handling and disposing of medical waste; providing such a system which facilitates the discharge of medical waste into a sewer system; providing such a system which can reduce the amount of disposable components associated with medical waste disposal; providing such a system which provides effective neutralization of various bacteria and infection sources; providing such a system which is usable by medical personnel with relatively little training; providing such a system with a control system which is at least partially automated; providing such a system which is relatively portable; providing such a system which is relatively compact; providing such a system which can be installed with relatively simple plumbing and electrical connections; providing such a system which is economical to manufacture and use, efficient in operation, capable of a long operating life and generally well adapted for the proposed usage thereof; providing a liquid medical waste disposal and canister flushing method; providing such a method which is relatively efficient; providing such a method which is relatively safe; providing such a method which is relatively economical and providing such a method which is particularly well adapted for the proposed usage thereof. 
     Other objects and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this invention. 
     The drawings constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a partially broken-away frontal perspective view of an embodiment of the liquid medical waste disposal and canister flushing system of the present invention. 
     FIG. 2 is a fragmented front sectional view of the liquid medical waste disposal and canister flushing system of FIG. 1 taken along line  2 — 2 . 
     FIG. 3 is a perspective view of the canister bracket and the lid removal bracket. 
     FIG. 4A is a bottom view of the canister bracket. 
     FIG. 4B is a sectional view of the canister bracket of FIG. 4A taken along line  4 B— 4 B. 
     FIG. 5 is a perspective view of the lid removal bracket. 
     FIG. 6 is a side view of the rotate bracket and the canister in their initial position with the canister lid attached to the canister. 
     FIG. 7 is a side view of the canister bracket and the canister in a rotated position and with the canister lid supported by the removal bracket. 
     FIG. 8 is a side view of the canister bracket and the canister in a 90 degree rotated position and the canister lid supported by the removal bracket. 
     FIG. 9 is a side view of the canister bracket and the canister in a rotated position for drainage and the lid removal bracket in a further rotated position where by the canister lid is positioned to fall off the removal bracket. 
     FIG. 10A is a perspective view of an alternative embodiment of the rotating mechanism with the canister rotation mechanism including a removal bracket combined with a lid grip to remove the canister lid from the canister. 
     FIG. 10B is an enlarged top view of the lid gripping mechanism for the removal bracket. 
     FIG. 11 is a schematic diagram of the plumbing system for the system of FIG.  1 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     A preferred embodiment of the system of the present invention is indicated in FIGS. 1 and 2. A cabinet  312  features an opening  314  that may be covered by a hinged lid  316 . A sink  320  is formed within the cabinet so that a chamber  322 , which may be accessed through opening  314 , is defined. The sink communicates with a drain  324  which leads to a plumbing system so that waste disposed in the sink is carried out of the hospital. As described in commonly-assigned U.S. Pat. No. 5,901,717, drain  324  may optionally communicate with a holding tank for treating the waste before it leaves the hospital. A control panel  326  is positioned upon the cabinet for ease of access by the system operator. 
     A canister rotation mechanism  330  is affixed to the cabinet  312  as best seen in FIG.  2 . The canister  350  is supported by a rotatable device such as a canister bracket  332  and the press fit canister lid  356  is supported by the lid removal bracket  338  of the canister rotation mechanism  330 . A disposal collection tray  328  is affixed to the cabinet  312 . The disposal collection tray  328  is positioned above the sink  320  and under the rotated position of the lid removal bracket  338  so that it receives the canister lid  356  after it falls from the lid removal bracket  338 . 
     The canister rotation mechanism for use in the system of FIG. 1 is indicated in general at  330  in FIG.  3 . The canister rotation mechanism  330  is connected to the cabinet  312  by a mounting bracket  340 . The rotation mechanism  330  includes the mounting bracket  340 , a motor  343 , pulleys  341 , timing belts  342 , a shaft  331  connected to a canister bracket  332 , and a shaft  336  connected to a lid removal bracket  338 . The shafts  331  and  336  are motorized and are connected via pulleys and timing belts such that the shafts simultaneously rotate the canister bracket  332  containing canister  350  and the lid removal bracket  338  holding canister lid  356  (shown in FIG. 7) in the same direction, e.g., clockwise. Alternative mechanisms, may be used to rotate the brackets, the canister and the canister lid such as a chain and sprocket, gears, or bearings, and the canister bracket may be rotated either before or after the lid removal bracket is rotated. 
     The canister  350  is also illustrated in FIG.  3 . The canister  350  includes a body portion  351  with a truncated, generally frustoconical shape. The canister  350  has an open top with three, equally spaced, horizontally extending tabs  352  that are positioned approximately one inch from the top of the canister  350 . The canister  350  also has a circumferential rim  353 . The canister may be molded from polycarbonate plastic, which is reusable and autoclavable up to 220° F., or other materials such as Radel plastic, which is autoclavable up to 321° F. 
     The canister bracket  332  is circular with an inner edge  346  and outer edge  347 . Also, as illustrated in FIG. 4A, the canister bracket  332  includes three notches  333  cut out of the inner edge  346  with slight ramp surfaces  335  positioned along the underside adjacent to the notches  333 . FIG. 4B is a sectional view of the canister bracket  332  taken along line  4 B— 4 B. FIG. 4B illustrates a slight ramp surface  335  adjacent to a notch  333  of the canister bracket  332 . 
     As seen in FIG. 3, the bottom surface of the lid removal bracket  338  is located above the canister bracket  332 . The canister lid  356  (FIG. 6) includes a circumferential lip  357  which rests on the lower rim  349  (FIG. 5) of the lid removal bracket  338  when the canister  350  is placed in the rotation mechanism. 
     FIG. 5 illustrates the details of the circular lid removal bracket  338 . An upper rim  348  and a lower rim  349  form the top surface. The lower rim  349  includes a slightly elevated portion  370  towards the back of the lid removal bracket  338 . The slightly elevated portion  370  assists in the removal of the canister lid when the canister is positioned in the canister bracket  332  and lid removal bracket  338 . The lower rim  349  also includes an indentation  372  in the front of the lid removal bracket  338 . The indentation  372  provides a guide for the canister when it is inserted into the canister bracket  332 . More specifically, one of the canister tabs, illustrated at  352  in FIG. 3, must be oriented to pass through the indentation  372  of the lid removal bracket  338  and the notch  333  (FIG. 4A) of the canister bracket  332  when the canister  350  is inserted in the cabinet  312  (FIG.  1 ). The lid removal bracket  338  also includes two upright projections  374  positioned on the upper rim  348  towards the back of the lid removal bracket  338 . The upright projections  374  direct the removed canister lid  356  when the lid removal bracket  338  rotates. 
     FIGS. 6 and 7 illustrate the canister lid  356  which includes a patient port  358  and a vacuum port  359  integrally molded onto the top surface of the canister lid  356 . The canister lid  356  is removably secured to the canister  350  in a press-fit fashion and has a lip larger than the rim of the canister  350 . The canister lid may be molded from, for example, polystyrene plastic. 
     As previously described in FIG. 5, the lid removal bracket  338  is a circular bracket. It includes an upper rim  348  and a lower rim  349 . The lower rim  349  allows the lower surface of the circumferential lip of the canister lid  356  to rest there when the canister  350  is positioned in the canister bracket  332 . The lid removal bracket  338  rotates in the same direction as the canister bracket  332  to a point where the lid  356  will fall off the lid removal bracket  338  into the disposal collection tray  328  (see FIGS.  8  and  9 ). 
     Once the material in the canister  350  is ready to be disposed of, the canister  350  is positioned within the canister bracket  332  with its three horizontally extending tabs  352  passing through the three notches  333  on the canister bracket  332 . (See FIG. 6) When the canister  350  with the lid  356  attached, is placed in the canister bracket  332 , the circumferential lip of the canister lid  356  rests on the lower rim  349  of the lid removal bracket  338 . The operator rotates the canister  350  about a vertical axis approximately 10 to 30 degrees counter clockwise so that the three horizontally extending canister tabs  352  travel along the ramp surfaces  335  of the canister bracket  332  until the horizontally extending canister tabs  352  are secured underneath the canister bracket  332 . As the canister  350  is turned it is forced downwardly away from the canister lid  356  as the lower rim  349  of the lid removal bracket  338 , including the slightly elevated portion  370 , pushes upwardly relative to the canister  350 , thereby loosening the attachment between the canister  350  and the canister lid  356 . The canister lid  356  is not removed by this action it is merely loosened. FIG. 6 illustrates an initial position of the canister  350  secured to the canister bracket  332  with the tabs  352  rotated in a locked position. 
     As seen in FIGS. 7-9, the canister bracket  332  and the lid removal bracket  338  rotate the canister  350  in the same direction but from different locations thereby forcing the canister lid  356  from the canister  350  and rotating the canister  350  to a drainage position. Once the canister  350  is rotated 90 degrees, as illustrated in FIG. 8, the canister lid  356  is completely removed from the canister  350  and supported by the lid removal bracket  338 . As illustrated in FIG. 9, the canister bracket  332  and lid removal bracket  338  continue to rotate until the canister  350  is rotated 180 degrees from the initial position and the canister lid  356  is positioned to drop by gravity, guided by upright projections  374 , into the disposal collection tray  328  positioned above the sink  320 . As the canister  350  is rotated, its contents empty into the sink  320 . 
     A spray system located within the sink and housing next applies a cleaning solution to the canister  350 . As illustrated in FIG. 2, the spray system includes a telescoping nozzle  318  and a rotating nozzle  319 . The telescoping nozzle  318  is positioned in the bottom of the sink  320 . The telescoping nozzle  318  extends up into the inverted canister  350  once the flushing cycle is activated. A solution is sprayed out of the telescoping nozzle  318  to clean the inside of the canister  350 . Rotating nozzle  319  is positioned near the back of the sink  320 . The rotating nozzle  319  sprays the solution on the outside of the canister  350  thereby cleaning the outside of the canister  350 . Once the spray system has cleaned the canister  350 , the canister  350  is rotated back to its initial position and it is ready for removal. 
     An alternative canister rotating mechanism is illustrated in general at  390  in FIG.  10 A. The rotating mechanism of FIG. 10A is similar to FIG. 3 except, that the removal bracket  392  includes a lid grip  394 . The canister lid  397 , in the alternative embodiment, includes a horizontal lid removal tab  396 . The lid removal tab  396  is molded with the canister lid  397  and extends in a radial direction from the edge of the canister lid  397 . As the canister  398  is turned into its locked position, upon insertion, the horizontal lid removal tab  396  slides in the lid grip  394 . As illustrated in FIG. 10B, the lid removal bracket  392  supports the lid grip  394  as the lid grip  394  clamps the lid removal tab  396 . The lid grip  394  clamps the lid removal tab  396  such that the lid grip  394  is connected to the bottom of the lid removal tab  396  near the inner edge of the lid removal tab  396  next to the canister lid  397  and the lid grip  394  is connected to the top of the lid removal tab  396  near the outer edge of the lid removal tab  396 . As the lid removal bracket  392  rotates, the lid grip  394  rotates until the canister lid  397  is no longer held in position by the lid grip  394 . Thus, the canister lid  397  falls into a disposal collection tray. 
     Operation 
     During a surgical procedure, a tube is connected between the vacuum port  359  and a vacuum source. A second tube is connected to the patient port  358  at one end while the other end is utilized by the surgeon or nurse to withdraw blood and fluids from the patient. When the surgical procedure is completed, or the canister is full, the tubing is disconnected from the vacuum and patient ports. The vacuum and patient ports are then capped so that the canister may be transported to and inserted in the rotating bracket mounted in the cabinet  312 . 
     With the canister secured within the canister bracket the cabinet lid  316  (FIG. 1) may be closed. This allows the drainage and flushing cycles to commence when the operator pushes a “start” button on the control panel  326 . When the “start” button is pushed the rotating mechanism rotates the canister from the initial position illustrated in FIG. 6 to the drainage position illustrated in FIG. 9, and the canister lid is rotated simultaneously from the initial position illustrated in FIG. 6 to the removal position illustrated in FIG.  9 . Alternatively, closing the cabinet lid may automatically activate the rotating mechanism so that the canister is rotated into the drainage position and the canister lid is rotated to the removal position. Either way blood and other fluids drain out of the canister into the sink  320  and down drain  324 . 
     A timed delay of the commencement of the flush cycle is provided after the canister is rotated into the drainage position. This delay permits substantially complete drainage of the liquid from the canister before the flush cycle commences. This delay may be accomplished through either an automated control system or manually via separate buttons for rotating the canister and commencing the flushing cycle. In the case of the latter, the operator may merely wait for the canister to drain before pushing the button to commence the flushing cycle. 
     Commencement of the flushing cycle causes the pressurized cleaning solution to enter the canisters via the spray systems that is positioned in the cabinet. The cleaning solution strikes the now inverted inside bottom of the canister. As a result, the contents remaining in the canister after drainage are disinfected and flushed down the drain  324 . 
     As a general guideline, it is desirable to flush the canister with a volume of solution equal to approximately 3 to 4 times its capacity. The cleaning solution mixture preferably comprises water and a suitable agent for killing virus and bacteria. For example, sodium hypochlorite (i.e., bleach) in a solution of about 1200 to 1400 parts per million with water has generally been found to be suitable. A delay of approximately 8 seconds has been found to be sufficient to drain the canister, and a flush cycle of approximately 45 seconds has generally been found to be sufficient. 
     Upon completion of the flushing cycle, the flow of diluted cleaning solution is stopped and the canister is rotated back to the initial position as illustrated in FIG.  6 . The canister lid may then be removed from the disposal collection tray and the canister may be removed from the rotating bracket by turning it clockwise to position the horizontally extending tabs in the notches. The operator can then lift the canister  350  from the canister bracket  332  and out of the cabinet. The canister lid may then be disposed of and the canister itself may be reused, if desired, at a fraction of the cost of disposing of complete canisters full of medical waste. 
     The solution mixture is preferably chosen to meet the particular objectives of a disposal and flushing system. For example, disinfection and flushing are generally the primary objectives with liquid medical waste containers, which for most reuse purposes do not have to be cleaned to the point where they would be considered sterile, since sterility is normally not required for liquid medical waste canisters. The lid would generally be considered “white” trash in medical facilities due to relatively low concentrations of liquid medical waste thereon and thus would not be subjected to the more stringent requirements typically in place for handling and disposing of the actual liquid medical wastes. 
     The flushed liquid medical waste from drain  324  mixes with the effluent from the medical facility in its plumbing drainage system and is normally discharged into a municipal sewer system at levels well below the maximums permitted for medical waste effluents. 
     The plumbing system of FIG. 1 is illustrated schematically in FIG.  11 . The plumbing system generally includes a water inlet line  20  connected to a suitable pressurized water source  21 , such as the normal municipal water service, a water tank or a water pump. A strainer  22  is provided in the water inlet line  20  and a backflow preventer valve  24  is provided downstream therefrom. 
     The water supply  28  includes a gate-type shut-off valve  30  and a solenoid-actuated valve  32  in line therewith. The water inlet line  20  ultimately communicates with junction  393  that communicates via cleaning solution injection lines  36  with an additive pump and reservoir  38 ,  39  that are housed within cabinet  312 . The reservoir preferably contains a cleaning solution for killing virus and bacteria (for example bleach) and a suitable defoamer. Activation of the pump causes the additives from the reservoir to mix with the water in the plumbing system so that a pressurized and diluted cleaning solution is emitted by the spray system in the cabinet. 
     An optional clot-dissolving solution source  40  communicates with a jet  42  directed into the subsink drain  324  and functions to dissolve blood clots in the drain. 
     A pressure flow sensor  201  monitors the flow of the solution into the cabinet. As described in commonly-assigned U.S. Pat. No. 5,901,717, a microprocessor may control valves  32  and the pump  39  to achieve the desired additive concentration. A remotely controlled emergency shut-off  211  allows the microprocessor to shut off the drain  324  as well as all fluid inputs in the event that monitored parameters are outside of predetermined limits. Additionally, a water flow sensor and a water temperature sensor maybe added to monitor the system. 
     It is to be understood that while certain forms of the present invention have been illustrated and described herein, it is not to be limited to the specific forms or arrangement of parts described and shown.