Device having tiltable and rotatable coacting wheels for projecting tennis balls

Claim 1

A ball projecting machine for ejecting tennis balls, and the like, of a selected substantially uniform compressible type comprising, in combination: a. a machine supporting frame; b. a vertical post means having an upper end rotatably supported by said frame for rotative swinging about a fixed vertical axis; c. a pair of motor mounts mounted on said post means at the lower end thereof and on opposite sides thereof, said post means providing means to enable said mounts to swing together about the vertical axis of the post means and to pivot on said post means about a horizontal axis passing through the lower end thereof; d. a pair of electrical drive motors each being mounted on a respective said motor mount and having driven shafts extending therefrom and rotating in opposite directions at a predetermined speed with the respective axes thereof posItioned parallel, laterally spaced, without lateral tilt and with a predetermined rearward tilt, said motors having in association therewith control means for controlling the energization and speed thereof; e. a pair of cylindrical-shaped rotatable ball ejecting wheels mounted on respective shafts of said motors and being swingable and pivotable with the motor mounts therefor about said respective vertical and horizontal axes, said wheels having ball engaging peripheral surfaces with a common central plane perpendicular to the axes of the wheels and of sufficient rigidity such that the outer surface of a ball may be at least slightly compressed when passing between said ball engaging surfaces; f. a ball feed structure including a ball receiving hopper supported on said frame above said wheels and having a ball entry aperture in the bottom thereof, an electrically driven apertured disc mounted on said frame below said ball entry aperture and having a predetermined number of apertures to sequentially receive and pass successive balls one at a time and at a predetermined rate, and having in association therewith control means for controlling the energization and speed of said apertured disc, a plate member fixed below and parallel to said disc and containing a ball aperture therein, a flexible elongated hollow feed tube mounted with a ball receiving end fixedly positioned below said apertured disc and aligned with said plate ball aperture to receive each said ball passed by said apertured disc and plate aperture in succession and with the opposite discharge end of said tube being directed between said wheels whereby to guide said balls through said tube to said wheels in the peripheral direction of said ball engaging surfaces whereby each ball when received, is at least slightly compressed between and is ejected from and free of said ball engaging surfaces at some predetermined speed, said feed tube being flexible so as to permit changes in the angle of rearward tilt of said wheel axes and with the discharge end thereof being secured to said motor mounts in a manner enabling said tube discharge end to swing and pivot therewith; and g. operator means mounted on said frame and operatively connected to swing and tilt said motor mounts about the respective said vertical and horizontal axes, said operator means including a first operator means connected to said motor mounts and adapted to pivot said motor mounts on said post means about said horizontal axis to adjust rearward tilting of said motor shaft and wheel axes and the vertical angle of ejecting a ball received between said wheels while causing said tube member to be appropriately flexed and its discharge end to be repositioned according to the amount of such adjustment and including a second operator means mounted on said frame arranged to swing said motor mounts about said post means vertical axis to adjust the horizontal positioning of said motor shaft and wheel axes and the horizontal trajectory of successive such balls, said second operator means includes a tracking type cam rotatably driven in coordination with said apertured disc, a lever having one end connected to follow the track of said cam, having an opposite end pivotally connected to a crank arm secured to said post means to swing said post means about its vertical axis and having a pivotal support block slidably and pivotally mounting said lever between said lever ends, said pivotal support block being positionable on said frame between said lever ends to control the amount said lever opposite end swings said crank arm and post means about said vertical axis as said lever one end tracks said cam.