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FIELD OF INVENTION 
     The present invention relates to recovery apparatus for pools and, more particularly, to apparatus for recovery objects, such as swimmers and bathers, quickly and safely from a pool. 
     DESCRIPTION OF PRIOR ART 
     Bathers and swimmers in trouble have relied in the past on splashing and shouting that they are in need of help. If noticed, they are thrown life saving jackets, floats, and/or ropes for rescue. However, in case of a heart attack, or cramps, the victim may not be able to shout for help, and notice as well as time is important for successful rescue. Also, quick physical help may not be available or competent. 
     The present invention seeks to provide pool recovery apparatus that avoids such troubles by, for example, rescuing a bather or swimmer in distress more quickly and efficiently than has been possible in the past. The invention also can be used to recover objects, such as toys, animals, and fish, from a pool. 
     SUMMARY OF THE INVENTION 
     In accordance with the present invention there is provided a signal sending device that is worn by a swimmer, which in case of distress is actuated to produce an electrical signal that is received by apparatus for automatically saving the swimmer. 
     The recovery apparatus comprises a net that normally rests on the bottom of a pool, for example, that automatically draws the swimmer in distress out of the pool, by operation of the apparatus that is remotely controlled by the distress signal. 
     The invention can be used to net any object animate as well as inanimate in a pool in a similar situation. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will now be described further, by way of example, by reference to the accompanying drawings, in which 
     FIG. 1 is a fragmentary perspective view of a distress signal transmitter; 
     FIG. 2 is a circuit diagram of the signal receiving apparatus; 
     FIG. 3 is a view partly in section of a pool provided with a new drawing apparatus shown in side elevation; 
     FIG. 4 is a schematic view of the net operating apparatus; 
     FIG. 5 is a view partly in side elevation and partly in cross section of a detail of a net control guide; 
     FIG. 6 is a cross sectional view of such guide taken on line A--A of FIG. 5; 
     FIG. 7 is a diagrammatic view of a time cycle for drawing the outer edge of the net upwardly and downwardly, parallel to the deep end wall of the pool; and 
     FIG. 8 is a similar view representing a time cycle controlling movement of the net backwardly as it is moved to draw an object from the pool, or automatically to place the net on the bottom thereof. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     A signal transmitter 10 is worn by a swimmer or bather, for example, by means of a belt 12. Such transmitter 10 is provided with a switch handle 14 for operation by the swimmer in case of distress, such as a cramp of heart attack. Such signal is picked up by a suitably tuned receiver 16 which thereupon energizes the coil 18 of a relay 20 by way of a circuit 22 that is connected to a suitable electrical supply source 24. This causes relay contact switch 26 to close, thereby energizing net operating apparatus circuit 28. 
     Such circuit 28 includes a switch 30 which connects the circuit 28 to a source 32 of electrical power 34, and test switches 36 and 38 for checking the operation of the apparatus. Indicators 40 including lights, bells, and sirens and/or meters are connected in the circuit 28 for indicating that the apparatus is in operation. 
     FIG. 3 shows how the cables 42 and 44 are connected to motors 46 and 48 for timed movement as they are driven forwardly and backwardly, under the control of timers 50 and 52 in circuit 28, FIG. 2. The timers 50 and 52 are mechanically connected at 54. 
     Referring to FIGS. 3, 7, and 8, the motors 46 and 48 are timed to move the upper cables 42 at a constant speed through forward increments A 1  -A 2 , A 2  -A 3 , etc., to A 10  -A 11 , while the lower cables 44 is moved first through reverse increments B 1  -B 4 , then at different forward speed increments B 4  -B 6 , B 6  -B 8 , and B 8  -B 10 . The forward constant speed of cables 42 is preferably two feet per second, while that of cables 44 is also two feet per second in moving through increments of B 6  -B 8  and B 8  -B 10 . Reverse speed of cables 44 is 1.5 feet per second in increment B 1  -B 4 , while their forward speed through increment B 6  -B 8  is four feet per second. This assures an untangled condition of the net as the object being recovered is drawn upwardly and above the pool. FIG. 4 shows how the upper cables 42, for example, is interconnected by a gear box 58 provided with cable pulleys 60 and 62. The gear box 58 is connected to a motor pulley 64. The cables 42 preferably are a flexible rod for movement through tracks 66 and 68 that are contoured to follow generally the adjacent surfaces of pool 70. 
     A detail of one of the tracks 66 and 68, for example, is shown in FIGS. 5 and 6. The track 66 is a pipe provided with a longitudinal slot extending along the side thereof facing the center of the pool 70, FIG. 3, for movement of a guide 74 having balls 76, 78 located within the track 66. One ball 78 is connected at 80 to a cable, or flexible rod 42, for example. An eye 82 on the guide 74 is used to connect a corner of the net 84 to the guide 74. Thus, the submerged ends of the net are connected to upper and lower guides for controlling movement of the net for placement on the bottom 86 of pool 70, as well as for the recovery of an object or being to be removed from the pool by pulling up the net in a gentle, quick and automatic way. 
     The invention is suitable for removing fish as well as inanimate objects from a pool. In the case of children, the apparatus can remove a child that is in trouble by a simple action of operating the switch worn by the child, or by a switch under the control of a babysitter watching the child. In the case of adults in a pool, an adult can be saved by simply operating the switch or other signal generating device worn by such adult, or one within reach of a person outside of the pool. 
     While the invention has been described by reference to a particular embodiment, it will be clear to those skilled in the art that various modifications may be made thereto without departing from the spirit and scope of the invention as set forth in the appended claims.

Summary:
A recovery apparatus in the form of a net that normally rests on a swimming pool bottom and automatically draws a swimmer in distress out of the pool water by rising to the top of the pool.