Abstract:
A rotor at the front of a tennis ball retrieving device is journalled for rotation in a direction whereby tennis balls lying at random on a tennis court or like surface are picked up and conveyed upwardly rearwardly to the top of a receptacle. An arcuate guide plate is provided for cooperation with the rotor and is positioned between the latter and the receptacle, the conforming guide plate being spaced from the rotor such as to form a ball transfer path therebetween. The path has a width less than the diameter of a tennis ball and extends from an upper point lying in a plane coinciding with the upper level of the receptacle to a lower point proximate ground surface. In operation, rotational forces exerted by the resilient rotor surface act upon the balls to raise the latter through the transfer path to the upper point thereof where such elevated balls are ejected in rearward direction, gravity causing the balls to drop into the receptacle. A pair of opposed diverging retriever arms are secured to the front end of the retrieving device to enlarge the effective sweep range thereof.

Description:
RELATED PATENTS 
     Apparatus for retrieving tennis balls which utilize rotary elements journalled for rotation in a direction whereby the balls are picked up and conveyed into a receptacle or receiving chamber, are disclosed in U.S. Pat. No. 3,485,398 issued Dec. 23, 1969 to Offner and in U.S. Pat. No. 3,593,868 issued July 20, 1971 to Folz. In addition, U.S. Pat. No. 3,102,647 issued Sept. 3, 1963 to Bonney discloses a similar system employing a rotary element to retrieve golf balls 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates generally to improvements in ball retrieving devices and more particularly to a tennis ball retrieving device having a high retrieval efficiency and improved ball entrainment and transfer means. 
     2. Description of the Prior Art 
     With the ever increasing boom in the sport of tennis, teaching sessions in this sport by tennis professionals are in great demand. Usually, large numbers of balls are used during such sessions. The tedious job of having to pick up the balls following one such session and prior to the next one and with the balls lying at random positions all over the court, becomes a time-consuming and strenuous task. Sometimes the retrieval of grounded balls is accomplished by picking the balls up by hand while in other instances mechanized ball retrievers are used. Such ball retrievers range from the conventional tennis ball pick up tubes and baskets to the more sophisticated retrieving devices which utilize rotary members which by rotational movement in a given direction automatically entrain and transfer the balls from the surface into a ball chamber or receptacle. Although developed to facilitate the retrieval of balls in a relatively short period of time, tennis ball retrievers presently used still pose a problem as regards their complex and intractable systems and parts combined with their low retrieval efficiency of tennis balls, taking into consideration that at the present time literally hundreds of balls are to be retrieved daily. 
     SUMMARY OF THE INVENTION 
     In accordance with the present invention, a tennis ball retrieving device is provided which overcomes the aforementioned problems and which satisfies the important criteria of being durable, simple in construction and having a high efficient retrieval of tennis balls. 
     The present invention further provides a tennis ball retrieving device which is easily invertible from a ball retriever to a ball dispenser. 
     According to the invention, the tennis ball retrieving device essentially comprises a rotor at the front of a tennis ball retrieving device and which is journalled for rotation in a direction whereby tennis balls lying at random on a tennis court or like surface are picked up and are conveyed rearwardly to the top of a receptable disposed rearwardly of the rotor. An arcuate guide plate is provided for cooperation with the rotor and is positioned between the latter and the receptable, the conforming guide plate being spaced from the rotor such as to form a ball transfer path therebetween. The path has a width less than the diameter of a tennis ball and extends from an upper point lying in a plane coinciding with the upper level of the receptacle to a lower point proximate ground surface. In operation, rotational forces exerted by the resilient outer rotor surface act upon the balls to raise the latter through the transfer path to the upper point thereof where said elevated balls are ejected in rearward direction, gravity causing the balls to drop into the receptacle. A pair of opposed diverging retriever arms are secured to the front end of the retrieving device to enlarge the effective sweep range thereof. 
     The width of the rotor can be dimensioned such as to enable a multitude of tennis balls to be picked up simultaneously and to be conveyed to the ball receptacle. 
    
    
     The above and still further objects, features and advantages of the present invention will become apparent upon consideration of the following detailed description of one specific embodiment thereof, especially when taken into consideration with the accompanying drawings. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an exploded perspective view of the tennis ball retrieving device embodying the invention; 
     FIG. 2 is a perspective view of the ball retrieving device of FIG. 1, the illustration showing the device inverted from its usual operating position to an upright or stand-up position in which the apparatus serves as a ball dispenser; and 
     FIG. 3 is a side elevational view, partially in section, of the ball retrieving device of FIG. 1. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to the drawings in which like reference numerals index like parts and with attention initially directed to FIGS. 1 and 3, there are shown a tennis ball retrieving device, referenced generally by the numeral 10, embodying the present invention. 
     The retrieving device 10 is seen to comprise a substantially elongated support frame 12 having a forward frame portion 14 and a rearward frame portion 16. In operating position the frame 12 extends generally in a horizontal plane parallel to ground level. Provided at the forward and rearward frame portions 14, 16 are a pair of roller members 18, 20, respectively, which enable movement of the device 10 over the surface of a field, tennis court, arena, or other area where it is desired to retrieve balls. Simultaneously, the roller members 18, 20 serve as supports for the device 10 with respect to ground. 
     A ball receptacle 22 is removably carried by a support frame 12 at a location generally midway of the frame. The effective receptacle area, however, is adjustable and may be enlarged as will hereinafter be described in detail. A generally U-shaped handle 24 is attached to rearward portion 16 of support frame 12 for the purpose of imparting motion of the device 10. 
     A rotary drum 26 is journalled in the frame forward portion 14 for rotational movement during operation of the device for picking up balls. The drum 26 is generally cylindrical and includes a pair of fixed shaft ends 28, one shown, at opposite ends of the drum and which extend in axial alignment. One of the shaft ends 28, for example the one shown, is provided with a sprocket wheel 30 which through a chain member 36 cooperates with a second sprocket wheel 32 mounted on a freely rotatable shaft which provides a bearing for one of the roller members 18, for example the one shown. As will be appreciated, the sprocket chain 36 is coupled to and interconnects the sprocket wheels 30, 32 in the usual manner. 
     As the device is pushed over a surface, e.g., in forward direction, the roller members 18, 20 are driven in counterclockwise direction and, by means of the sprocket drive arrangement 30, 32 and 36 in cooperation with one of the shafts of roller members 18 and drum 26, simultaneous rotational movement in corresponding rotation direction is transmitted to the drum. 
     Typically, the roller members 18 are in the form of a pair of wheels journalled on opposite sides of forward portion 14 of support frame 12 for free rotation such as by a pair of axially aligned shaft members 34, only one shown. The shafts 34 are disposed in substantial axial alignment and are rotatably secured to a pair of frame side plates 38, 40 attached to the frame forward portion 14 at opposite sides thereof. The manner of rotatably mounting the shafts 34 on the side plates 38, 40 may be done in any well-known manner, not shown. 
     In the arrangement shown, the roller members 20 are journalled at opposite sides of rearward portion 16 of support frame 12 at the lower elements thereof. The roller members 20, typically, are swivel wheels of the caster-type supported by the frame via bracket members 42, 44 for universal pivoting or rotation of facilitate moving or rolling of the device 10 across ground surface. 
     The support frame 12 is seen to include a pair of parallel opposed side structured formed by a pair of longitudinally extending upper bar members 46, 48, a pair of longitudinally extending lower bar members 50, 52, and a plurality of upright bar members 54 interconnecting the respective upper and lower bar members 46, 48 and 50, 52, the latter having removably attached thereto a pair of diverging retriever arms, described hereinafter. The frame side structures are spaced apart by a plurality of transversely extending bar members 56, the latter forming the frame bottom which supports the receptacle 22. Additional transversely extending, parallel bar members 58, 60 are provided adjacent the frame forward and rearward portions 14, 16, respectively, and which extend in spaced apart relation across the frame 12, at a height midway between the upper and lower members 46, 48 and 50, 52. The parallel spaced bar members 58, 60 respectively form the forward and rearward boundaries for the ball receptacle 22 and which prevent the latter from shifting in the longitudinal direction relative to the frame. The overall dimension of the receptacle 22 closely corresponds to the generally rectangular frame receptacle area defined by the bottom bar members 56, and the side- and forward and rearward bar members 46, 48 and 58, 60, respectively. In case a receptacle of greater capacity and, hence, of greater dimension is desired, it is only necessary to enlarge the effective ball receptacle area on the frame to enable such an enlarged receptacle to be carried by the frame. This is accomplished by adjusting the given distance between the bar members 58, 60. As shown in FIG. 1, the transverse bar member 60 is adjustably mounted on a pair of crossbar members 62, 64 extending in the elongation of the frame, transversely intermediate the upright bar members 54a, 54b and 54c, 54d, respectively. The bar member 60 is slidably movable along the members 62, 64, lengthwise relative to the frame and is operative to enlarge the given receptacle area to a point bounded by the bar members 54b, 54d, the latter forming the rearward extremity of the frame. Positioning means in the form of clamp members 66, 68 are secured to the outer opposite ends of the transverse bar member 60 and serves to retain the latter member in a desired position relative to the bar members 62, 64. 
     As clearly shown in FIG. 1, the ball receptacle 22 is in the form of a basket of the open-wire type. The basket is seen to comprise four side panels 70, 72 and 74, 76, a bottom 78 and an upper lid 80. The lid 80 is pivotally mounted at 82 to the upper receptacle element 84, enabling the lid 80 to be opened and closed, as required. For example, in operating position the lid is in open position and rests backwardly on the upper receptacle element 84. In non-operating position, for example when the device 10 is inverted from a ball retriever to a ball dispenser as shown in FIG. 2, the lid is closed. In the illustration shown in FIG. 2, the device is placed in an upright ball dispensing position with the lid 80 in closed position to prevent unwanted escape of balls from the receptacle. To enable dispensing of the balls from the receptacle in the position shown, also the rearward panel 74 is arranged to be moved between an open and closed position about a pivot 86 at the lower or bottom receptacle element 88, as viewed in FIG. 1, in which condition the panel 74 is pivoted backwardly through 180° and rests against the bottom of the frame rearward portion 16. To adequately support the device 10 in the dispensing position of FIG. 2, a pair of tubular extension members 46a, 48a are removably attached to the forward extremities of bar members 46, 48. 
     The handle 24, as shown, is pivotally mounted at 90, 92 at the upper extremities of the bar members 54b, 54d. The pivots 90, 92 enable the handle to be pivoted, for instance, to the position shown in FIG. 2, thereby facilitating easy dispensing of the balls from the receptacle. 
     Provided directly forwardly of the receptacle 22 and immediately adjacent the rotary drum 26 at the frame forward portion 14 is an arcuate guide plate member 94 made, typically, of sheet metal. The guide plate 94 is mounted in spaced relation relative to the rotary drum 26 and extends forwardly downwardly from a point coinciding with the plane of the upper receptacle element 84 to a point in close proximity with ground surface. Typically, the clearance between the lowest guide plate point 97 and ground is about .25&#34;. The guide plate 94 and the drum 26 are mounted intermediate the frame side structures at the forward portion 14 of the frame. The guide plate 94 is stationary and is fixedly secured at its upper end to the frame transverse bar member 58 and at its lower end is secured to the frame structure at a point behind the side plates 38, 40. 
     The rotary drum 26 includes a main body 96 covered with a layer or mass of resilient material 98, typically a foam material. In a preferred arrangement of the invention, the layer of foam material has a thickness of 1 inch. The drum has a highest point disposed in a plane substantially higher than the upper level or top of the receptacle which, as indicated hereinbefore, coincides with the highest point of the guide plate. The lowest point of the drum is disposed directly adjacent ground. Typically, the drum has a circumferential dimension of approximately 34 inches and the clearance between the lowest drum point and ground surface is approximately 2.25 inches. Also, according to the invention, the spacing between the inner guide plate surface and opposing drum wall is less than the diameter of a tennis ball. The lowest point 97 of the guide plate 94 is disposed proximate the lowest point of the drum. When the device is moving forwardly, counterclockwise rotational movement is imparted to the rotary drum and any ball resting in the path of the drum is engaged thereby and swept rearwardly into engagement with the arcuate guide plate 94. At this point, the ball has entered the transfer path 100 formed by the spacing between the guide plate 94 and drum 26 and is frictionally carried upwardly rearwardly to the upper extremity 102 of the guide plate where it is released from engagement with the drum and guide plate, whereupon due to gravitational forces acting upon the ball, the latter drops backwardly into the receptacle. 
     During the transfer of the ball through the transfer path 100, considerable rotational forces are created between the ball and drum due to compression of the foam layer 98 and, to a lesser degree, compression of the tennis ball itself. As a result, the balls are efficiently and positively directed through the spacing or transfer path 100 and, upon reaching the uppermost extremity 102 of the guide plate, are ejected from the spacing upwardly and rearwardly relative thereto and, due to gravity, collected in the receptacle. 
     The drum width may be chosen such as to collect a multitude of balls in a matter of seconds. For example, it has been found that with a drum width of about four feet, a multitude of balls in excess of 300 may be collected within less than 30 seconds. 
     As shown, the rotation axes of the drum 26 and wheels 18 are disposed in substantial parallelism, with the axes 28 of the drum extending through the frame side plates 38, 40, the latter being secured to upright bar members 54e, 54f at the frame forward portion 14. 
     To increase the width of the sweep of the device 10, a pair of forwardly extending diverging arm members 104, 106 are removably secured to diverging frame portions 108, one shown, at the forward end of the frame 12. The frame portions 108 are welded to the lower ends of the bar members 54e at the frame forward extremity. The arm members 104, 106 may be pivotally or otherwise connected such as, for example, by means of a wing nut arrangement 110. If pivotally secured, the arm members 104, 106 may be pivoted upwardly to an out-of-the-way position if desired. The arm members 104, 106 preferably are disposed at an angle of 30° with respect to a horizontal plane parallel to ground level. A wheel or roller 112, 114 is provided on each of the arm members and is preferably journalled in the proximity of the outer ends thereof. The wheels 112, 114 are mounted for rotation about an axis perpendicular to the horizontal and normal to the rotation axis of the drum. The wheels 112, 114 may serve as bumpers or may be operative to dislodge balls from tight corners or balls lying against vertical walls or wire structures or prevent entanglement of the arm members 104, 106 with upstanding wire structures such as nets, fences, and the like. 
     Although the invention has been described as being embodied in a tennis ball retrieving device, it will be appreciated that the principle underlying the novel structural arrangement of the ball retrieving elements which forms the inventive portion of this application may equally beneficially be applied to retrieving apparatus for balls other than tennis balls. 
     From a detailed consideration of this description, it will be apparent to those skilled in the art that this invention may be employed in a number of different ways through the use of routine skill in this field. For this reason, the present invention is not to be considered as being limited except by the appended claims defining the invention.