Abstract:
A toilet venting apparatus includes an upper insert mountable between a toilet tank and a toilet bowl, and a lower insert mountable between the bowl and a floor sewer pipe. The upper insert cooperates with the toilet bowl for removal of gases in the bowl through apertures in the bowl rim. A motor driven fan extracts the gases through the upper insert and forces the gases along the lower insert into the sewer. The fan is remotely activated. Flushing the toilet disables the fan until reactuated following flushing.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This Continuation-In-Part application claims priority from United States Provisional Patent Application No. 60/083,690 filed Apr. 30, 1998 titled Odour Venting For Toilets and U.S. patent application Ser. No. 09/300,446 filed Apr. 29, 1999 now U.S. Pat. No. 6,073,273. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to a selectively operable hydraulically actuated venting apparatus for flush toilets which removes air from the bowl of the toilet through the flush passages located around the upper interior perimeter of the toilet bowl. In particular, manual activation of the venting cycle precedes the flushing cycle of the toilet and actuation of the toilet flush lever cancels the venting cycle. 
     BACKGROUND OF THE INVENTION 
     A basic North American toilet consists of two major components, a tank and a bowl. The rectangular tank has an approximate capacity of two gallons of water. Connected to the tank is a water line which provides a pressurized source of clean water to the tank. The water stored in the tank empties into the bowl through an aperture controlled by a tank or ball valve. A chain is attached at one end of the chain to a flush handle on the outside of the tank. The other end of the chain is attached to the tank valve. Actuating, the flush handle pulls the chain and lifts the tank valve to allow water from the tank through the aperture and into the bowl. A float is also attached to the flushing system in the tank, which gauges when sufficient water has refilled the tank and allows the tank valve to close over the aperture into the bowl. 
     The bowl is located below the tank. The bowl may approximate a hemispherical shape. A seat is fitted to the upper edge defined by the planer circumference of the hemisphere. The bottom of the bowl has an aperture which cooperates with a pipe, the pipe forms an upside-down U-shape located directly behind the bowl. The top or apex of the inverted “U” is higher than the bottom of the bowl. The pipe continues down to an exit aperture connected to the sewer pipe opening in the floor. The toilet bowl is mounted over the sewer pipe opening. Water in the bowl and in the pipe will be at the same level, leaving an air pocket in the top of the inverted “U”. The air pocket allows for a siphoning action required for flushing. 
     Water flowing from the tank down into the bowl causes a surge in the bowl. The surge causes water to push into the pipe, upwards around the apex of the “U” in the pipe, pushing the air pocket down into the sewer. This creates a siphon which draws a continuous flow of water from the tank into the bowl and through the pipe. When the tank empties so that there is no more water in the bowl, air fills the “U” in the pipe, stopping the siphon. Once the siphon is interrupted, water fills the tank and re-fills the bowl. The water stops flowing into the bowl when the float in the tank rises with the water level in the tank to a high enough level which allows the tank valve to close. The water level will find itself between the bottom of the bowl and a horizontally equal level in the lower leg of the pipe. 
     In the prior art, applicant is aware of U.S. Pat. No 5,257,421 which issued Nov. 2, 1993 to Rose et al for an Air Fresh Toilet. Rose et al disclose the use of a toilet bowl having an auxiliary passageway built-in to the rear of the bowl and housing a water driven ventilation fan thereon. Water valves are coupled to use of the toilet seat so that weight placed on the seat initiates the fan turbine which runs the fan until the weight is removed from the seat. The disclosed design of the bowl requires that a conventional toilet bowl has to be entirely replaced, rather than providing for retrofit to conventional toilets as in the present invention. 
     SUMMARY OF THE INVENTION 
     In summary, the toilet venting apparatus of the present invention includes an upper insert mountable between a toilet tank and a toilet bowl, and a lower insert mountable between the bowl and a floor sewer pipe. The upper insert has a first aperture therethrough cooperating between a flush valve aperture in a lower wall of the tank and a water-entry aperture in an upper surface of the bowl. The water-entry aperture cooperates, via a manifold in the bowl, in fluid communication with water dispensing apertures around an upper rim of the bowl. 
     A flush valve in the tank is actuable so as to release flush water held in the tank through the flush valve aperture, the first aperture, the water-entry aperture, the manifold and the water dispensing apertures to thereby flush the toilet. The upper insert has a first conduit in fluid communication with the first aperture. The first conduit extends from the first aperture to a first outlet. The first outlet opens externally from the upper insert. The lower insert has a second aperture therethrough cooperating between a down-leg discharge aperture of the bowl and an inlet aperture of the floor sewer pipe. The lower insert has a second conduit in fluid communication with the second aperture. The second conduit extends from the second aperture to a second outlet. The second outlet opens externally from the lower insert. 
     A third conduit is mountable in fluid communication between the first and second outlets. A water driven turbine is mounted to the third conduit. A water supply is mounted to an impeller side of the turbine. An actuator, for biasing to an open position a water supply valve is mounted on the water supply. The water supply water is fed under pressure to the impeller side of the turbine. Water flows through a nozzle to thereby turn an impeller of the turbine. The impeller is co-axially mounted to a fan of the turbine. The fan is in fluid communication with the third conduit. 
     Thus, when the first insert is mounted between the tank and the bowl, and when the second insert is mounted between the bowl and the floor sewer pipe, and when the third conduit is mounted to the first and second outlets, turning of the impeller turns the fan so as to draw air into the third conduit from the bowl. Air is drawn from the bowl via the water dispensing apertures, the manifold and the first conduit. The fan urges the air down the third conduit, so as to pass through the second conduit and into the floor sewer pipe. 
     In one aspect of the present invention the actuator is a manual water supply valve actuator manually operable between first and second water supply valve biasing positions. In the first water supply valve biasing position the water supply valve is biased into the open position. Operation of a flush valve linkage for actuating the flush valve biases, by a return actuator cooperating with the flush valve linkage, the manual water supply valve actuator from the first water supply valve biasing position to the second water supply valve biasing position. In the second water supply valve biasing position the water supply valve is biased into a closed position. 
     In a further aspect, the manual water supply valve actuator is a plunger. The plunger is mounted to a first end of a mechanical water supply valve linkage. An opposite second end of the water supply valve linkage is mounted to the water supply valve in cooperation therewith for opening and closing the water supply valve upon corresponding translation of the plunger. The plunger is cooperatively mounted to a flush valve linkage actuator. When the plunger is in the first water supply valve biasing position, the flush valve is closed and the flush valve linkage is in a non-actuating state. Actuation of the flush valve linkage by the flush valve linkage actuator, so as to open the flush valve, actuates the return actuator so as to bias the plunger into the second water supply valve biasing position. 
     In yet a further aspect, the manual water supply valve actuator includes a mechanical water supply valve linkage wherein a first portion of the linkage is contained within the tank, a second portion of the linkage, contiguous to the first portion, passes through a sealed first aperture in the tank, and a third portion of the linkage, contiguous to the second portion, extends from the sealed aperture to the water supply valve. The manual water supply valve actuator also includes a water supply valve linkage actuator cooperatively mounted to an end of the first portion of the linkage, opposite the second portion. The water supply valve linkage actuator is mounted through a second aperture in the tank. 
     In one embodiment of the present invention the mechanical water supply valve linkage is a flexible cable slidably mounted in a flexible cable cover. The cable cover is mounted at a first end to the second, or an upper, aperture in the tank. The plunger is journalled in the upper aperture and mounted at an inner end thereof to a corresponding first end of the flexible cable. The cable cover passes through the first, or a sealed lower, aperture in the tank. It extends to, and is mounted at, the water supply valve at a second end of the cable cover opposite the first end of the cable cover. A corresponding second end of the flexible cable cooperates with the water supply valve for opening and closing thereof. 
     Advantageously, the first or sealed lower aperture is formed in a tank mounting bolt, and the second or upper aperture is formed in the flush valve linkage actuator. Further, the flush valve linkage actuator is a lever and the water supply valve linkage actuator is a plunger having a push button at an outer end thereof, opposite the inner end. The push button has an edge thereof overlapping a portion of the lever. The return actuator is a wedge mounted between the portion of the lever and the edge of the push button. Rotation of the lever so as to actuate the flush valve linkage drives the wedge under the edge of the push button urging the push button outwardly of the lever thereby actuating the plunger into the first water supply valve biasing position. 
     In yet a further aspect of the present invention the upper and lower inserts are generally planar rigid members having secondary apertures for accepting mounting bolts therethrough. In particular, in one embodiment the upper and lower inserts are pedestals sized to generally correspond, respectively, to the size of the bases of the tank and bowl. 
     Further advantageously, the first and second conduits each have cavity portions extending as cavities through the corresponding generally planar rigid members. Rigid tube portions, contiguous to the corresponding cavity portions, extend from the cavity portions to the corresponding first and second outlets. The third conduit is a rigid tube, and the water turbine is mounted in a rigid housing at an upper end thereof. 
     In a further and alternative embodiment of this invention, the fan is driven by a mechanical drive means and the water supply valve is no longer required. The cable cover and mechanical linkage actuator, previously extending to the water supply valve, now extends directly from the sealed lower aperture formed in a tank mounting bolt to the upper end of the third conduit. The upper end of the third conduit has both a fan housing and a drive housing. The fan housing contains a fan, which is in fluid communication with both the first aperture formed in the upper insert and the water entry aperture in the upper surface of the bowl. Drive means is located in a separate drive housing so as to be isolated from the fan housing. Drive means, for example, in the form of a helical or leaf spring, can be tensioned by a user and is connected through an arrangement of gears to operate the fan. A second end of the mechanical linkage actuator projects into the drive housing for selectively regulating the release and operation of the tensioned spring. 
     In a yet further alternative embodiment of this invention, drive means is in the form of a battery operated electrical motor and the mechanical linkage actuator selectively closes electrical contacts permitting rotational output from the motor to operate the fan. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIGS. 1A,  1 B and  1 C depict, in cut-away side elevation view, the operation of a conventional prior art toilet. 
     FIG. 1 is an exploded isometric view illustrating the components of the venting apparatus in relation to a standard flush toilet. 
     FIG. 2 is a side elevational view, partially cut-away, of a standard flush toilet with the venting apparatus in place. 
     FIG. 3 is a front elevational view, partially cut-away, of a standard flush toilet with the venting apparatus in place. 
     FIG. 4 is an enlarged detailed view of a portion of FIG.  3 . 
     FIG. 5 is a plan view of the upper insert portion of the venting apparatus of the present invention. 
     FIG. 6 is a sectional view along line  6 — 6  of FIG.  5 . 
     FIG. 7 is a plan view of the lower insert portion of the venting apparatus of the present invention. 
     FIG. 8 is a sectional view along line  8 — 8  of FIG.  7 . 
     FIG. 9 is an isometric view, partially cut-away of the impeller and fan housing. 
     FIG. 10 is a sectional view at the upper end of the vent pipe. 
     FIG. 11 is an enlarged view of the control valve of the present invention illustrating the valve in the open position. 
     FIG. 12 is a sectional view of the control valve illustrating the valve in the closed position. 
     FIG. 13 is an enlarged perspective view of the flush handle of FIG.  1 . 
     FIG. 14 a  is an enlarged sectional view of the flush handle and integral valve operating button, with the button in the valve open position. 
     FIG. 14 b  is a sectional view of the flush handle illustrating the button in the valve closed position. 
     FIG. 15 is an isometric view of the stationary portion of the flush handle illustrating the button retraction mechanism. 
     FIG. 16 is an isometric view of the modified fan and drive housing for a mechanically operated drive means. 
     FIG. 17 is a partially sectioned front view along line  17 — 17  of FIG.  16 . 
     FIG. 18 is a sectional view along line  18 — 18  of FIG.  17 . 
     FIG. 19 is a sectional view along line  19 — 19  of FIG.  17 . 
     FIG. 20 is a sectional view along line  20 — 20  of FIG.  17 . 
     FIG. 21 is a side view of the operating handle partially in sectional view. 
     FIG. 22 is a sectional view along line  22 — 22  of FIG.  21 . 
     FIG. 23 is an enlarged view of a portion of FIG.  19 . 
     FIG. 24 is an enlarged view of a portion of FIG.  20 . 
     FIG. 25 is a partially sectioned front view of the modified fan and drive housing for an electrically operated drive means. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     As seen in FIGS. 1A,  1 B and  1 C, prior art toilet  10 ′ has a tank  12 ′ and a bowl  14 ′. Water  16 ′ in tank  12 ′ flows into bowl  14 ′ in direction A′ when tank valve  18 ′ is opened. Water is directed around the rim  20 ′ of bowl  14 ′ and flows into the bowl via a spaced-apart array of apertures under the rim. Water is also directed so as to flow upwardly in direction B′ along up-leg  22 ′ of pipe  24 ′. This floods pipe  24 ′ so as to force the air pocket around apex  26 ′ in pipe  24 ′, down the down-leg  28 ′ of pipe  24 ′ and into sewer pipe  30 ′, and causes a siphon effect which draws water continuously along pipe  24 ′ into sewer pipe  30 ′ until water is drained from bowl  14 ′ and tank  12 ′. 
     As may be seen from the accompanying drawings the hydraulically actuated venting device  10 , of the present invention, is connected to the water supply line  12  for the flush toilet through an auxiliary tee  14 . A control valve  16 , which is operated by rotation of a flush handle  18  mounted to the toilet tank  8 , allows selective operation of the venting device  10  by the user. Control valve  16  is rigidly mounted relative to the toilet by being threaded onto the outwardly projecting end of a hollow tank hold down bolt  20 . A flexible tube  21  extends between the inner end of hold down bolt  20  and flush handle  18 . This arrangement permits a valve operating push rod  22 , slidably journalled in tube  21 , to pass through the toilet tank from flush handle  18  to control valve  16 . 
     An upper insert  24  is fitted to the rear portion of the toilet bowl  6  and supports the toilet tank  8 . A compartmentalised housing  26  contains a water driven impeller  28  and fan  29  (both shown in dotted outline in FIG. 9) mounted on a single axle for co-operative rotation. Housing  26  is mounted underneath and to the rear of upper insert  24 . A lower insert  30  is positioned below the toilet bowl, between the toilet and the floor, and is connected to the impeller and fan housing  26  by a connecting vent pipe  32 . The use of upper insert  24  and lower insert  30  allow venting device of the present invention to be retrofitted to conventional toilets. 
     Upper insert  24  has a through-aperture  34  which is conically shaped on its internal upper surface so as to cooperate with flush valve assembly  25 . A conical gasket  25   a  forms a seal between the walls of aperture  34  and the discharge tube  25   b . A lock washer threads onto the lower end of the discharge tube which projects downwardly from the bottom of tank  8 . The underside of upper insert  24  has a projecting cylindrical lip  36  which has an annular recess  38  near the open end. This annular recess retains a lower gasket  40 . Projecting lip  36  and gasket  40  mate with and seal the water entry aperture  6   a  located at the rear of the toilet bowl  6 . Upper insert  24  has an internal passage  42  (shown in dotted outline in FIG. 5) which connects aperture  34  in fluid communication with a vent opening  44  located on the underside of upper insert  24 . Inlet  26   a  of housing  26  mates into vent opening  44 . 
     Lower insert  30  has a projecting lower lip  54 . Through-aperture  50  extends through lower base  30  and lower lip  54 . Lower lip  54  mates with floor waste pipe  48 . An upper surface of aperture  50  mates with the toilet discharge aperture  52  which protrudes below toilet bowl  6 . An annular recess  56  seen in FIG. 8 retains a compressible gasket  58 . Lip  54  and gasket  58  provide a seal with floor waste pipe  48  when mated therein. Lower insert  30  has an internal passage  60  (seen in dotted outline in FIGS. 7 and 8) which connects aperture  50  in fluid communication with vent opening  62  located at the distal end of conduit  61  on lower insert  30 . The lowermost end of pipe  32  mates onto vent opening  62 . 
     The control valve  16  as illustrated in FIGS. 11 and 12 has a through-passage  70 . Water from the water supply line  12  flows, via tee  14  and water take-off line  15 , in direction A through control valve  16 . Valve  16  is actuated by movement of pushrod  22  which may be a covered flexible cable and which extends from valve  16  to flush handle  18 . The end  72  of push rod  22  is slidably fitted within valve  16  at right angles to passage  70 . End  72  has aperture  74  formed therethrough in alignment with through-passage  70 . End  72  of pushrod  22  has seals  76  positioned on either side of aperture  74 . These seals prohibit water from flowing from passage  70  through hollow bolt  20  into the tank of the toilet. Alignment of aperture  74  in the end  72  of push rod  22  with through passage  70  in the control valve  16  permits water to flow to, so as to spray onto, impeller  28  in housing  26 . As may be seen in FIG. 12, as pushrod  72  is drawn in direction B toward flush handle  18  during the rotation of flush handle  18 , through passage  70  is sealed off stopping water flow through valve  16 . 
     When the control valve  16  is in the open position, water passes via hose  17  from valve  16  to a nozzle  80  secured within the fan and impeller housing  26 . Impeller  28  is rotated by water pressure from a spray of water from nozzle  80 . Water is directed from impeller  28  downwardly through vent pipe  32 . Flap valve  82  (shown in dotted outline in FIG. 1) is rotatably mounted near the upper end of the vent pipe  32 . Water exiting housing  26  causes flap valve  82  to open. 
     As noted above, fan  29  and impeller  28  are mounted on a common shaft  84 . Thus they co-operatively rotate, meaning that as impeller  28  rotates so too does fan  29 . As impeller  28  is driven by water pressure from nozzle  80 , fan  29  is rotated to draw air in direction D through the bowl chamber or manifold (hereinafter collectively manifold  6   b ) from the flush water discharge apertures  85  at the upper rim of the toilet bowl  6 , as illustrated in FIG.  2 . It is understood that, although only two such apertures are illustrated, there are a plurality of them in radially spaced array around the rim of the bowl. Air, which is intended to be odorous air from inside bowl  6 , is drawn through firstly, apertures  85 , then through internal passage  42  within upper insert  24  (seen in FIG.  6 ), so as to exit through aperture  44  into inlet  26   a  of housing  26 . The air is forced downwardly by fan  29 , through vent pipe  32 , to exit, co-mingled with the water dropping from impeller  28 , into sewer waste pipe  48  through lower insert  30 . 
     Air is prevented from being drawn through overflow pipe  86  (seen in dotted outline in FIGS. 2 and 3) in the toilet tank  8  by a water trap  88 . Flap valve  82  advantageously forms a tight seal within vent pipe  32  when the venting device is not in use to inhibit backflow of sewer gases. The flap valve may be of a design known in the art. Alternatively to accomplish the tight seal, as seen in FIG. 10, a depression  83  is formed in the upper surface of flap valve  82 . Depression  83  retains a small amount of water and thus urges, by its weight, the flap valve downwardly in direction E about its pivots  82   a  to firmly seat the valve against the inner walls of vent pipe  32 . Other actuating arrangements may be employed as would be known to one skilled in the art. For example, a mechanically actuated grate valve or shutter valve may be employed along the lines taught in the United States patent to Rose et al discussed above. A mechanical linkage may be taken off, for example, push rod  22 . 
     As seen in FIGS. 13-15, flush handle  18  includes a mounting sleeve  90 , which is non-rotatably secured to toilet tank  8  for example by means of a nut  91  threaded onto the inner end of the sleeve. An operating lever  92 , has an elongate hollow shaft  94  inserted through the mounting sleeve and rotatably secured therein by a clip  96  or the like. Clip  96  is fitted over the inner end of hollow shaft  94 . Push button  98  is slidably secured within the operating lever for rotation therewith as the lever is rotated to operate the flushing mechanism. Push button  98  is mounted on operating lever  92 , for co-operative rotation therewith, within a mating annular collar  93 . A lock pin  100  projects from operating lever  92  into a corresponding recess within push button  98 . Button  98  is secured within annular collar  93  by a retaining ring  102 . Button  98  has secured to its inner end valve operating rod  22  which passes through flexible tube  21  and hollow tank hold down bolt  20  into operating valve  16 . 
     Mounting sleeve  90  has at its outer end a plate  95  which is drawn against tank  8  by the action of tightening nut  91  onto the inner end of the sleeve. An arcuately shaped push button reset wedge  104  is formed on plate  95 . Reset wedge  104  slidably engages reset arm  106  on button  98 . When button  98  is pushed inwards in direction F, valve operating rod  22  is advanced to open valve  16 . When button  98  is in the reset position as shown in FIG. 14 b  valve  16  is in the closed position of FIG.  12  and handle  20  may be operated to flush the toilet without opening the valve  16  or operating the fan. Only when the button is depressed by the user will operating rod  22  be advanced to open the valve and permit water to flow to drive impeller  28  to thereby activate the venting operation. When the button  98  is in its depressed position the rotation of the lever  92  in a normal manner, when flushing the toilet for example, will reset the button and close valve  16  thereby terminating the venting operation. 
     An alternative embodiment  110  of this invention is illustrated in FIGS. 17 through 24, where the hydraulic means for actuating the venting apparatus has been replaced with a mechanical or “clock work” actuating means. Compartmentalised housing  26  contains a mechanical drive means  112  and fan  29  in discrete compartments  26   a  and  26   b  respectively. Only fan compartment  26   b  is connected in pneumatic communication with aperture  34  of upper insert  24  and vent opening  62  of lower insert  30 . 
     Primary shaft  118  is installed within compartment  26   a  of housing  26  for rotation by rotation of an operating lever  114 . Rotation of lever  114  in direction F causes cooperative synchronous rotation of primary shaft  118  by virtue of the locking action resulting between ratchet pawl  120  pivotally positioned in primary shaft  118  and internal ring gear  122  formed in operating lever  114 . Counter-rotation of operating lever  114 , in a direction opposite to direction F, results in a slight counter-rotation of ratchet pawl  120  permitting internal ring gear  122  to slide past pawl  120  without rotation of shaft  118  occurring. Ratchet pawl  120  is rotationally urged in direction F by a coil spring mounted to its pivot shaft to ensure minimum rotational movement when handle  114  is rotated in direction F. Fixedly mounted to primary shaft  118 , for rotation therewith, also in direction F, is gear  118   a.    
     A secondary shaft  126  has gear  126   a  fixedly mounted thereto which is in meshing contact with gear  118   a  for cooperative but counter-rotation therewith in direction G. Also fixedly mounted to shaft  126  is drive spring housing  128  which has a ring gear  130  formed on its external surface. Freely rotatably positioned on secondary shaft  126  is drive gear  132  which has an integrally formed hub  134 . Drive spring housing  128  is open-faced adjacent to gear  132  and hub  134  nests within this recess. A helical drive spring  136  is also nested within the recess of housing  128  surrounding hub  134 . Drive spring  136  has its outermost terminus fixed to housing  128  and its innermost end secured to hub  134 . 
     Rotation of primary shaft  118  in direction F by operation of handle  114  in turn counter-rotates secondary shaft  126  in direction G. As drive spring  136  becomes tensioned, a second ratchet pawl  140  mounted within housing  26  and in meshing contact with ring gear  130  on drive spring housing  128  prohibits rotation of secondary shaft  126  in a direction opposite to direction G. Drive spring  136  now transfers rotational force to drive gear  132  which is freely rotatably mounted on secondary shaft  126 . 
     Rotation of drive gear  132  is controlled through movement of pushrod  22 , which may be a covered flexible cable, which extends from the mechanical drive means compartment  26   a  to flush handle  20 . The end  72  of pushrod  22  is connected to a locking lever  138  which is pivotally mounted within compartment  26   a . As flush handle  20  is operated, pushrod  22  is drawn outwardly from compartment  26   a , in direction H, as button  98  is engaged by reset wedge  104 . This results in the rotation of lever  138  into positive contact with drive gear  132 , thus preventing rotation of drive gear  132 . Only when button  98  is pushed in a direction opposite to direction H will lever  138  be released from engagement with drive gear  132  to permit free rotation of gear  132 . 
     Fan  29  is fixedly mounted to shaft  142  which extends from fan compartment  26   b  into drive means compartment  26   a . Shaft  142  has fan drive gear  144  fixedly mounted thereto in meshing engagement with drive gear  132 . 
     When button  98  of flush handle  20  is pushed inwardly to commence the venting cycle rotation of drive gear  132  results in the rotation of fan drive gear  142  and fan  29 . 
     It will be noted that a rotational advantage for tensioning drive spring  136 , through operation of handle  114 , can be derived by ensuring that the diameter of gear  118   a  is significantly larger relative to gear  126   a . More efficient operation of fan  29  can be achieved where drive gear  132  is larger relative to gear  144 . Sizing of drive spring  136  ensures that fan  29  rotates for a satisfactory length of time. 
     In a further embodiment of the invention seen in FIG. 25, the mechanical means for actuating the venting apparatus has been replaced with an electrically powered motor  150  which derives power from batteries  152 . Drive gear  118   a  fixedly mounted to the drive shaft  156  of motor  150 , engages fan drive gear  144  secured to fan drive shaft  142 . Electrical contacts  160  are closed by end  72  of pushrod  22  when button  98  of flush handle  20  is pushed inwardly to commence the venting cycle. As flush handle  20  is operated, pushrod  22  is drawn outwardly from compartment  26   a , in direction H, as button  98  is engaged by reset wedge  104 . This results in opening of contacts  160  and cessation of the venting cycle. 
     It is anticipated that the batteries  152  may be rechargeable and a simple solar panel  162  connected to the electrical circuit would prolong the battery charge. 
     As will be apparent to those skilled in the art in the light of the foregoing disclosure, many alterations and modifications are possible in the practice of this invention without departing from the spirit or scope thereof. Accordingly, the scope of the invention is to be construed in accordance with the substance defined by the following claims.