the present invention provides a ball gathering and court drying system for installation in a tennis court or the like . referring first to fig1 a , there is shown a top plan , schematic view of a portion of a tennis court with a simplified representation of a first embodiment of the ball gathering and court drying apparatus in accordance with the invention , generally at reference number 100 . a portion of a tennis court 102 having a net 104 supported by support posts 106 is shown schematically . tennis court 102 has various markings 108 disposed on an upper surface thereof . none of tennis court 102 , net 104 , support posts 106 , or markings 108 form any part of the invention but are included to illustrate the intended operating environment for the ball gathering and court drying system in accordance with the invention . an air supply sub - system 120 is disposed along a right edge 110 of tennis court 102 and is substantially parallel to right edge 110 . as discussed in more detail hereinbelow , air supply system is designed for installation beneath the surface of tennis court 102 . air supply sub - system 120 has an air supply plenum 122 disposed therealong . one or a series of nozzles 124 are spaced along and connected to plenum 122 . plenum 122 is typically a cylindrical pipe having a relatively large diameter to minimize air pressure drop therealong . it will be recognized that a tapered plenum could be substituted to also control pressure drop . consequently , the invention is not considered limited to any particular plenum cross - sectional geometry . the invention is intended to include rather any plenum cross - sectional geometry . valves 126 , best seen in fig4 as well as fig3 a - 3d are inserted between plenum 122 and one or more nozzles 124 . air , represented schematically by arrows 128 is forced out of one or more nozzles 124 in a direction parallel to the major axis , not specifically identified of one or more nozzles 124 . air 128 pushes any balls 112 across tennis court 102 . a single ball 112 a is shown schematically on tennis court 102 in a multi - image dashed pictogram depicting ball 112 a &# 39 ; s movement across the tennis court 102 in the direction shown by arrow 114 . the air supply apparatus 120 is housed in a trough 130 of sufficient width and depth to contain plenum 122 and one or more nozzles 124 as well as a lift mechanism , best seen in fig2 a and 2b and discussed in detail hereinbelow . a ball collection sub - system 140 is disposed at the left edge , not specifically identified , of tennis court 102 . ball collection system 140 is aligned substantially parallel to air supply sub - system 120 . ball collection sub - system 140 may be implemented as a simple trough 142 downwardly slopping toward a vertical ball conveyor system 150 or , in alternate embodiments , as a mechanical conveyor 146 , best seen in fig1 d that moves balls 112 toward vertical conveyor 150 . a vertical conveyor 150 at the terminus 142 of trough 140 and , when present , the terminus of horizontal conveyor 146 , best seem in fig1 d , accepts balls 112 and lifts them upward to a discharge chute 152 where they are discharged into a ball container 154 . referring now also to fig1 b , there is shown a first alternate embodiment of the ball gathering and court drying apparatus in accordance with the invention , generally at reference number 200 . ball gathering and court drying system 200 is similar to system 100 of fig1 a in most respects . a portion of a tennis court 102 having a net 104 supported by support posts 106 is shown schematically . for clarity , net 104 is shown as a solid line and posts 106 are not labeled in fig1 b . tennis court 102 has various markings 108 disposed on an upper surface thereof . none of tennis court 102 , net 104 , support posts 106 , or markings 108 form any part of the invention but are included to illustrate the intended operating environment for the ball gathering and court drying system 200 in accordance with the invention . an air supply sub - system 120 is disposed under net 104 . like in system 100 of fig1 a , air supply system 120 is designed for installation beneath the surface of tennis court 102 . air supply sub - system 120 has an air supply plenum 122 disposed therealong . a first series of one or more nozzles 124 a pointing in a first direction away from net 104 are interspersed with a second series of one or more nozzles 124 b pointing in an opposite direction relative to the first series of one or more nozzles 124 a . one or more nozzles 124 a and 124 b are spaced along and connected to plenum 122 . plenum 122 is typically a cylindrical pipe having a relatively large diameter to minimize air pressure drop therealong . valves 126 , best seen in fig4 as well as fig3 a - 3d , are inserted between plenum 122 and one or more nozzles 124 exemplified by nozzles 124 a , 124 b . air , represented schematically by arrows 128 is forced out of one or more nozzles 124 a , 124 b in directions perpendicular net 104 . air 128 pushes any balls 112 along tennis court 102 . a single ball 112 a is shown schematically on tennis court 102 in a multi - image dashed pictogram depicting ball 112 a &# 39 ; s movement along tennis court 112 a in the direction shown by arrow 114 . the air supply apparatus 120 is housed in a trough 130 of sufficient width and depth to contain plenum 120 and one or more nozzles 124 a , 124 b as well as a lift mechanism , best seen in fig2 a and 2b and discussed in detail hereinbelow . a ball collection sub - system 140 is disposed at each end of tennis court 102 , only one shown in fig1 b . ball collection systems 140 are aligned substantially parallel to air supply sub - system 120 . ball collection sub - systems 140 may be implemented as simple troughs 142 downwardly slopping toward a vertical ball conveyor system 150 . in alternate embodiments , a mechanical conveyor 142 , best seen in fig1 d , may be used to move balls 112 toward vertical conveyor 150 . it will be recognized that the nozzle configuration as shown in fig1 b may be combined with the arrangement shown in fig1 a disposed parallel to the edge of tennis court 102 . such an arrangement could be used to clear balls or water from two adjacent tennis courts , not shown . referring now also to fig1 c , there is shown a second alternate embodiment of the ball gathering and court drying apparatus in accordance with the invention , generally at reference number 300 . ball gathering and court drying system 300 is similar in some respects to portions of both systems 100 and 200 of fig1 a and 1b , respectively . a portion of a tennis court 102 having a net 104 supported by support posts 106 is shown schematically . none of tennis court 102 , net 104 , or support posts 106 , form any part of the invention but are included to illustrate the intended operating environment for the ball gathering and court drying system 300 in accordance with the invention . an air supply sub - systems 120 a , 120 b are disposed along a respective left edge 110 a and a right edge 110 b of tennis court 102 and are substantially parallel to left and right edges 110 a , 110 b . as discussed in more detail hereinbelow , air supply systems 120 a , 12 b are designed for installation beneath the surface of tennis court 102 . each air supply sub - systems 120 a , 120 b has an air supply plenum 122 a , 122 b disposed therealong . a series of one or more nozzles 124 are spaced along and connected to air plenums 122 a , 122 b . plenums 122 a , 122 b are typically cylindrical pipes having a relatively large diameter to minimize air pressure drop therealong . it will be recognized that a tapered plenum could be substituted to also control pressure drop . consequently , the invention is not considered limited to any particular plenum cross - sectional geometry . the invention is intended to include rather any plenum cross - sectional geometry . valves 126 , best seen in fig4 as well as fig3 a - 3d are inserted between plenum 122 and one or more nozzles 124 . also a shown in fig4 , one or more nozzles 124 are adapted to sweep from left to right in a plane substantially parallel to the upper surface , not specifically identified , of tennis court 102 . typically , valves 126 are used to selectively supply air from respective air plenums 122 a , 122 b to valves 124 . by synchronizing the supply of air with the sweeping motion of the valve , balls may effectively be swept from tennis court 102 for collection by a ball collection sub - system 140 disposed at each end , neither specifically identified , of tennis court 102 , sweeping motion and selective supply of air to the valves is controlled by control system 500 , best seen in fig6 . the air supply apparatuses 120 a , 120 b are housed in troughs 130 a , 130 b , respectively , of sufficient width and depth to contain plenums 122 a , 122 b and nozzles 124 as well as a lift mechanism , best seen in fig2 a and 2b and discussed in detail hereinbelow . in this embodiment , air may be alternately supplied to plenums 120 a , 120 b , typically in short bursts . air , represented schematically by arrows 128 is forced out of one or more nozzles 124 in a direction depending upon the particular rotated position of one or more nozzles 124 at any particular point in time . one or more nozzles 124 typically move between two extreme positions : ( a )— a very small angle relative to the net , i . e . almost parallel to the net , typically 3 - 5 °; and ( b ) almost perpendicular to the net , typically 45 - 85 ° with respect thereto . it will be recognized that other ranges of nozzle rotation may be chosen to meet a particular operating circumstance or environment and the invention is not considered limited to the specific range of rotation chosen for purposes of disclosure , air 128 pushes any balls 112 down the tennis court 102 ( i . e ., away from the net towards ball collection sub stems 140 at each end of tennis court 102 ). the travel of tennis balls is anticipated to in zigzag patterns generally away from the net 104 and towards ball collection sub - systems 140 at each end of tennis court 102 . a single ball 112 a is shown schematically on tennis court 102 in a multi - image dashed pictogram depicting ball 112 a &# 39 ; s zigzag movement towards the end of tennis court 102 in the direction shown by arrows 114 . a ball collection sub - system 140 is disposed at the bottom edge , not specifically identified , of tennis court 102 . ball collection system 140 is aligned substantially perpendicular to air supply sub - system 120 . ball collection sub - system 140 may be implemented as a simple trough 142 downwardly slopping toward a vertical ball conveyor system 150 or , in alternate embodiments , as a mechanical conveyor 146 , best seen in fig1 d that moves balls 112 toward vertical conveyor 150 . it should be noted that in the embodiment of fig1 c , balls 112 moving along trough 142 must pass under ball container 154 . as methods of elevating ball container 154 to provide clearance for balls 112 to pass beneath it are considered to be well known to those of skill in the art , such methods or mechanisms are not further discussed herein , a vertical conveyor 150 at the terminus 144 of trough 142 and , when present , the terminus of horizontal conveyor 146 , best seem in fig1 c , accepts balls 112 and lifts them upward to a discharge chute 152 where they are discharged into a ball container 154 . referring now also to fig1 d and 1e , there are shown top plan , schematic views of a belt conveyor and a cleated conveyor system , respectively . in alternate embodiments , ball collection sub - system 140 may include a conveyor 146 , to move balls 112 along in a direction indicated by arrows 156 . such conveyors overcome possible problems with rubbish build up in trough 142 . in fig1 d a belt conveyor 146 is disposed in trough 142 . in fig1 e , a cleated belt conveyor having cleats 148 disposed on the belt conveyor 146 to provide positive drive to balls 112 as they are moved along the horizontal conveyor in the direction shown by arrows 156 . it will be recognized that horizontal ball conveyor systems shown in fig1 d and 1e are also applicable to the first embodiment of the ball collection and court drying system on fig1 a . a ball barrier 184 or 186 is disposed proximate either an outside edge of trough 142 ( fig1 f and 1g ) or within trough 142 ( fig1 h and 1i ). a vertical conveyor 150 at the terminus 144 of trough 140 accepts balls 112 and lifts them upward to a discharge chute 152 where they are discharged into a ball container 154 . it is assumed that identical vertical conveyors 150 are disposed at each end of the tennis court . it will be recognized that a single vertical conveyor may be located at just one end of tennis court 102 and a ball conveying system , either above ground or beneath ground , neither shown , may be used to transfer collected balls 112 from a first trough 142 at a first end of tennis court 112 to the second trough 142 at an opposite end of tennis court 102 . the plenum 122 , nozzles 124 , 124 a , 124 b , and valves 126 form an air distribution system structure that is typically disposed underground when not in use and selectively elevatable when needed to clear balls or water from the tennis court . referring now also to fig1 f and 1g , there are shown end elevational , schematic views of a first embodiment of a ball barrier 184 in a closed , inoperative position and an open , operative position , respectively . ball barrier 184 is pivotally disposed over trough 142 ( fig1 g ) at a pivot or hinge 188 . when required to stop balls 112 from rolling beyond trough 142 , it may be rotated upwardly to a substantially vertical position as shown in fig1 g . while no specific mechanism is show for moving ball barrier 184 from a closed to an open position , it is believed that such mechanisms are well known to those of skill in the art and as such , the mechanism in not further described or discussed herein . referring now also to fig1 h and 1i , there are shown end elevational , schematic views of a second embodiment of a ball barrier 186 in a lowered , inoperative position and an raised , operative position , respectively . ball barrier 186 is disposed within trough 142 ( fig1 h ) in a lowered , inoperative position . when required to stop balls 112 from rolling beyond trough 142 , it may be raised vertically to an operative position as shown in fig1 i . while no specific mechanism is show for lifting ball barrier 186 from a lowered to a raised position , it is believed that such mechanisms are well known to those of skill in the art and as such , the mechanism in not further described or discussed herein . referring now also to fig2 a and 2b , there are shown side elevational , cross - sectional , schematic views of a single nozzle 124 , valve , 126 , and plenum 122 , generally at reference number 200 . valve 126 is connected to air plenum 122 by a plenum outlet pipe 132 . fig2 a shows nozzle assembly 200 in a lowered , non - operational position while fig2 b shows nozzle assembly 200 in a raised , operational position . a trough 130 houses the plenum 122 , plenum outlet pipes 132 , valves 126 , and one or more nozzles 124 on a lifting mechanism 138 . a lifting cradle 136 is interposed between lifting mechanism 138 and plenum 122 . a cover 134 sized and configured to seal trough 130 when the air supply sub - system 120 is in a lowered , non - operational position . cover 134 rests on cutaway areas in the top of trough 130 and is adapted to be substantially flush with the surface of tennis court 102 . as is seen in fig2 b , air supply sub - system 120 is shown in an elevated , operational position . lift mechanism 138 may be implemented in many ways known to those of skill in the art . a simple scissor jack type mechanism is shown for purposes of disclosure . while no power source is shown operably connected to lift mechanism 138 , it will be further recognized that an electric motor , a pneumatic motor , a hydraulic motor , or other types of actuators believed to be well known may be used to selectively actuate lift mechanism 138 . consequently , the invention is not considered limited to the scissor jack type lift mechanism . rather , the invention includes any and all suitable lift mechanisms . likewise , the invention is not considered limited to any particular actuator operably connected to lift mechanism 138 . rather the invention includes any and all suitable actuating mechanisms . valves 126 may be implemented as electrically , pneumatically , or hydraulically actuated solenoid valves or as other types of valve . one possible valve construction is a movable shutter selectively placed in front of nozzles 124 to block or moderate the flow of air from one or more nozzles 124 . valves 126 may be connected for individual actuation or , in alternate embodiments , valves may be grouped so that multiple valves are actuatable . referring now also to fig3 a and 3b , there are shown front elevational schematic views of a representative shutter valve , generally at reference number 250 . in fig3 a , a shutter 162 is shown in a closed position thereby blocking the air flow from a nozzle 124 . in fig3 b , shutter 162 is shown in an open position whereby air may escape from nozzle 124 . a lip 160 along a major axis of trough cover 134 stabilizes shutter 162 while in a closed position as seen in fig3 a . a lever 166 is operatively connected to shutter 162 . a pivot 168 in lever 166 allows shutter 162 to rotate thereabout in response to movement of lever 166 . a lever actuation band 170 extends along an upper surface of a base 176 , typically forming part of plenum lifting cradle 136 . a lever - engaging plate 172 is affixed to an upper surface of lever actuation band 170 , typically with screws 174 or other fasteners . it will be recognized that other attachment methods such as adhesive fastening , welding , or other type of fasteners may be substituted for screws 174 used for purposes of disclosure . base 176 , supports a lever 166 rotatable on a pivot 168 . lever 166 has a shutter disc 162 attached to a distal end thereof . moving the proximal end of lever 168 by moving lever - engaging plate 172 affixed to an upper surface of lever actuation band 170 in a direction shown by arrow 178 a causes shutter 162 to move from a closed position as seen in fig3 a to an open position as shown in fig3 b . shutter 162 is moved from a closed position to an open position by moving lever actuation band 170 and lever - engaging plate 172 in a direction shown by arrow 178 b . lever actuation band 170 is operably connected to an actuator , not shown , that is disposed to reciprocally move lever actuating band 170 as shown by arrows 178 a and 178 b . it will be recognized that actuators may be implements as bi - directional pneumatic or hydraulic cylinders ; electrical solenoid arrangements , linear stepper motors , and other electrically , pneumatically , or hydraulically powered actuators . such actuators are believed to be well known to those of skill in the art and , consequently , are not further described or discussed herein . in still other embodiments , the actuation system might be designed wherein shutters 162 are maintained in a closed position by one or more springs , not shown , and then opened by movement of shutter engaging plates 172 and shutter operating band 170 . an embodiment wherein shutter operating band moved in only a single direction and as shutter engaging plates 172 moved past , the spring ( s ), not shown , returned shutters 168 to their nominally closed position . actuation of shutter operating band may be simplified in that a simple electric motor may be utilized to move shutter operating band 170 . referring now also to fig3 c and 3d , there are shown side elevational views of the representative shutter valve of fig3 a and 3b , respectively . in all discussions heretofore , one or more nozzles 124 have been assumed to be fixed in a forward or rearward orientation . it is possible that one or more nozzles 124 be rotatable so as to reciprocally move across a certain arc , thereby facilitating “ sweeping ” balls 112 from the tennis court 102 . referring now also to fig4 , there is shown a top plan , schematic view of a nozzle 124 moveable from side to side . lawn sprinklers adapted for such reciprocal motion controlled by stops at each limit of the desired sprinkler head travel are believed to be well known . the implementation of such lawn sprinkler heads is believed to be transferable to one or more nozzles 124 . it will be recognized that many other possibilities for sweeping some or all of one or more nozzles 124 across controlled arcs and any suitable mechanism for so doing may be substituted . in fig4 , a nozzle 124 is attached to rotation mechanism 182 and is shown in an un - rotated , position pointing straight outward . rotation mechanism 182 is operatively connected to a controller 502 , best seen in fig6 , via a connection 524 . a control signal , not shown , selectively applied by controller 502 via connection 524 causes nozzle 124 to move ( i . e ., sweep ) between positions indicated by nozzles 124 a and 124 b shown in broken lines . while an angle of approximately plus or minus 30 ° from the straight forward position is shown in fig4 , it will be recognized that many other sweep angles may be chosen to meet a particular operating requirement . consequently , the invention is not considered limited to the approximately plus or minus 30 ° sweep range chosen for purposes of disclosure . rather , the invention is intended to cover any angular sweep range . rotation mechanism 182 is connected to a valve via a flexible connection 180 . valve 126 is shown with a connection 518 that provides a control signal from controller 502 . while an electrically actuated valve is shown for purposes of disclosure , as discussed hereinabove , a pneumatically or hydraulically controlled and / or actuated valve may be substituted . consequently , the invention is not considered limited to the implementation chosen for purposes of disclosure but rather it is intended to include any and all suitable nozzle sweeping mechanisms . sweeping the nozzles may be useful for dislodging tennis balls close to air supply sub - system 120 but between nozzles . sweeping the one or more nozzles may also be useful when the ball collection and court drying system is used in court drying only mode as discussed in more detail hereinbelow . referring now also to fig6 , there is shown a greatly simplified system block diagram of the ball collection and tennis court drying system in accordance with the invention , generally at reference number 500 . heretofore the air source for operating the ball collection and court drying system has not been discussed . in one embodiment , a large multi - stage centrifugal compressor may be used to supply large volumes of relatively low pressure air to plenum 120 . with this type of air flow , the system could be operated continuously for several minutes to clear or dry the court . in an alternate embodiment , the ball collection and court drying system could be operated in a “ single shot ” mode . in this type of operation , a large reservoir of relatively high pressure compressed air is created by one or more relatively small compressors . once the reservoir is at an intended pressure , the air may be released to the one or more nozzles as a short blast at high pressure to clear and / or dry the court . in this embodiment , a large air reservoir is disposed away from plenum 122 . it is possible to use the plenum 122 as part of the air reservoir to reduce the size of the external tank ( i . e ., reservoir ). in alternate embodiments , it is possible to increase the size of plenum 122 so as to completely eliminate the need for an external tank altogether . referring now also to fig5 a there is shown a simplified system block diagram of a compressor - based air supply system , generally at reference number 400 . an air compressor 402 has an output connected to an output pipe 406 that is , in turn , connected to an air reservoir tank 404 . a control signal 508 generated by master controller 502 is supplied to compressor 402 . it will be recognized that compressor 402 requires a power source . an appropriate power source is assumed to be present and forms no part of the invention . a pressure regulator 418 is generally inserted inline in output pipe 406 . typically , pressure regulator 418 will have an operative connection , not shown , to compressor 402 . an optional air pressure gauge 408 is connected to tank 404 . in addition , a safety relief valve 410 is also connected to tank 404 . an output pipe 412 conducts air from air reservoir tank 404 to an optional “ dump ” valve 414 . dump valve 414 is selectively actuated in response to a signal received from master controller 502 . the air output from dump valve 414 is connected to air plenum 122 . referring now also to fig5 b , there is shown a simplified system block diagram of a blower - based air supply system , generally at reference number 420 . the compressor 402 of fig5 a is replaced by a blower 422 in this embodiment . the need for a reservoir tank 404 , a pressure gauge 406 , and a pressure relief valve 410 is completely eliminated and the output of blower 422 is connected directly to air plenum 122 by an output duct 424 . a control signal 508 generated by master controller 502 is supplied to blower 422 . it will be recognized that blower 422 requires a power source . an appropriate power source is assumed to be present and forms no part of the invention . referring now also to fig6 , there is shown a simplified system block diagram of a control system , generally at reference number 500 . the entire ball collection and court drying system is operated by control system 500 . a master controller 502 is typically controlled by one or more control panels 504 . it will be recognized that many possible configurations for control panel 504 interacting with master controller 502 are possible . for example , full control may be exercised from a control panel , not specifically identified , located in an office or other administrative facility with a control panel , not specifically identified , having only partial control and disposed near each tennis court . for purposes of disclosure , a single control panel 504 is shown schematically connected to master controller 502 . details of a typical control panel are shown in fig7 . a control line 506 operatively connects compressor or blower 402 to master controller 502 . a control line 508 operatively connects lift mechanism 138 to master controller 502 . a control line 510 connects ball return conveyor 146 to master controller 502 . a control line 512 connects vertical conveyor 150 to master controller 502 . a control line 514 connects master controller 502 to a nozzle valve controller / sequencer sub - system 516 . nozzle valve controller / sequencer is anticipated to be a programmable unit that defines the way air is applied to one or more nozzles 124 by controlling groups of valves 126 . one function of nozzle valve controller / sequencer 516 is to control whether the full tennis court 102 or only a portion thereof is cleared . the court portion typically is one half the tennis court 102 . various patterns may be pre - programmed to control the sequence of air application to one or more nozzles 124 or groups of one or more nozzles 124 . an output bus 518 connects nozzle valve controller / sequencer 516 to individual valves 126 , each valve 126 or preselected group of valves 126 having a conductor , not specifically identified , in output bus 518 . an output connector 520 connects master controller 502 to a swivel controller / sequencer 522 that controls the swivel mechanisms 182 associated with particular one or more nozzles 124 . like nozzle valve controller / sequencer 516 , a swivel controller / sequencer 522 is anticipated to be a programmable unit that defines movement of individual or possible groups of nozzles 124 . swivel controller / sequencer 522 controls the sweep range by setting left and right swivel stop points , not specifically identified , for the angular movement of one or more nozzles 124 . an output bus 524 connects swivel controller / sequencer 522 to individual , rotation mechansims 182 or preselected groups of rotation mechansims 182 having a conductor , not specifically identified , in output bus 524 . master controller 502 may incorporate an audible / visible alert 528 to notify persons in the vicinity of tennis court 102 when the ball gathering and court drying system is about to be activated . such warning is appreciated when an implementation using a release of compressed air is in use as the sound of the air release may be relatively loud . referring now also to fig7 , there is shown a schematic representation of a possible embodiment of a control panel 504 . control panel 504 has a master switch 530 , represented in fig7 as a key switch . a blower ( or compressor in alternate embodiments ) on - off switch 532 has indicator lamp 534 adjacent thereto . an additional indicator lamp 536 illuminates when a compressed pressure in reservoir tank 404 is sufficient to perform a single shot air release . another switch 538 turns horizontal ball conveyor 146 on and off . an indicator lamp 538 indicates when horizontal ball conveyor 146 is operating . a switch 542 raises and lowers air supply sub - system 120 . an indicator lamp 544 illuminates when air supply sub - system 120 is raised . a court selection switch 550 allows selection of left half 552 , full court 555 , and right court 554 operation a switch 556 “ arms ” the nozzles . an indicator lamp 158 illuminates when the nozzles are armed to allow a single shot release of air to be triggered . the arming operation could include moving shutter 162 from the front of one or more nozzles or any other preliminary operations necessary for a single shot air blast mode of operation . a switch 560 starts nozzle sweeping . an indicator lamp 562 illuminates when nozzles are sweeping . a fire button 564 initiates a one shot air release . prior to the actual release , an audible / visible alert may be actuated for several seconds to alert persons near the court to be cleared or dried that a loud sound is imminent . after a several second delay , dump valve 414 is opened . while conventional toggle switches have been chosen for purposes of disclosure , many alternatives are possible for control panel 504 . for example , a touch screen display , not shown , may be used to implement the illustrated functions . it will be recognized that alterations may be made to control panel 504 to adapt it for controlling a blower - base , continuous air release system . such changes are considered obvious to persons of skill in the art and are not discussed in further detail herein . it will be further recognized that semi - automatic or fully automatic control systems may be implemented to allow provide a “ single button ” to cycle the ball collection and court drying system by providing sequences operation of each component of the system at an appropriate time . since other modifications and changes varied to fit particular operating requirements and environments will be apparent to those skilled in the art , the invention is not considered limited to the example chosen for purposes of disclosure , and covers all changes and modifications which do not constitute departures from the true spirit and scope of this invention . having thus described the invention , what is desired to be protected by letters patent is presented in the subsequently appended claims .
a pneumatic ball gathering system that clears tennis balls from a tennis court using air supplied to at least one discharge nozzle with optional intervening valves forming a structure that is typically disposed underground and selectively raised to clear balls . in one implementation , the structure is located along one side edge of the tennis court . in an alternate implementation , the structure may be located under the net and be configured with at least one nozzle disposed to direct air in both directions away from the net . a collection trough formed with a slope to cause collated balls to roll downward therein is disposed opposite the at least one nozzle . an optional mechanical conveyor system is placed in the trough to move collected balls to a predetermined location . a vertical conveyor raises balls for discharge into an appropriate container . the system may be used to facilitate drying the court after rain .