Title:
BALL RECEIVING, METERING AND PROJECTING SYSTEM
United States Patent 3815907
Abstract:
An improved ball receiving and projecting system of the type having a detachable, foldable receiving net, a stand-mounted ball projector, and upwardly foldable trough wings, additional features being a ball-metering unit adapted to receive balls alternately from the trough wings and to meter the balls out to the projector at uniform intervals; an improved trough having co-acting Y- and U-section portions, a unique ball-shed over the central portion of the trough, and simplified articulated structure are also disclosed.
US Patent References:
Table tennis practice device
Lohr - July 1962 - 3043592
Ball throwing machine and target net
Cook - March 1968 - 3375005
Table tennis practice device
Lohr - July 1962 - 3043592
Ball throwing machine and target net
Cook - March 1968 - 3375005
Application Number:
05/307611
Publication Date:
06/11/1974
Filing Date:
11/17/1972
View Patent Images:
Export Citation:
Primary Class:
Other Classes:
124/51.100, 221/237, 124/1
International Classes:
A63B69/40; A63F9/02; A63B47/02; A63B47/00; A63B39/00
Field of Search:
273/30,102.4,29A,26D,101,129 124/26,1,6,51R 209/202 198/52 221/277,237
Primary Examiner:
Pinkham, Richard C.
Assistant Examiner:
Brown, Theatrice
Attorney, Agent or Firm:
Mcclellan Sr., John F.
Claims:
What is claimed and desired to be secured by United States letters patent is
1. In a ball receiving and projecting system having a ball projector, a ball chute running past the ball projector for feeding balls to be projected and for directing balls projected, a ball trough having front and rear walls and ends, including a pair of wings inclined to a central trough portion having rearward opening for feeding balls to the ball chute, a screen positioned above the ball trough for deflecting balls downward into the ball trough, and a support for the system, the improvement comprising: means for selectively receiving balls alternately from the respective ball trough wings and for ejecting balls in the order selectively received at uniform intervals through said rearward opening into the ball chute, including a disk positioned with the axis thereof parallel with the ball trough and the circumference adjacent the middle of the rearward opening in the ball trough, a semi-circular-section inclined trough member fixed in co-axial spacing around the bottom of the disk and extending upwardly to a position proximate the bottom of the rearward opening in the ball trough, a shaft affixed to the disk along the disk axis, a motor, means connecting the motor for rotation of the disk about the shaft, said motor arranged to rotate in a direction causing the periphery of the disk to move in the upward direction in passing the rearward opening in the ball trough, and first and second lobes on the respective first and second sides of the disk, each said lobe extending from the axis of the disk toward the periphery of the disk in a direction opposite to the extension of the other said lobe.
2. In a ball receiving and projecting system as recited in claim 1, each said lobe defining a surface having a curvature radially of the axis in a direction contrary to the direction of disk rotation and having a width extending in a direction substantially parallel with the disk axis, thereby defining a radially convex ball-urging surface.
3. In a ball receiving and projecting system as recited in claim 2, each radially convex ball-urging surface having a radially extending groove therein, for thereby centering balls on the ball urging surface.
4. In a ball receiving and projecting system as recited in claim 3, the transverse-section shape of each wing of the ball trough comprising a "Y" section with the lower portion thereof being proportioned to prevent any balls which may be received therein from lying side-by-side thereacross, thereby insuring tandem delivery of balls through each respective wing of the ball trough.
5. In a ball receiving and projecting system as recited in claim 4, a gable roof ball shed positioned over the central portion of the ball trough, with a side of the roof sloping downward toward each wing of the ball trough, thereby providing for shunting balls into the trough which might otherwise enter the top of the means for receiving balls from the trough.
6. In a ball receiving and projecting system as recited in claim 5, the central portion of the ball trough being lower than the wings of the ball trough and the wings of the ball trough respectively having downturned inner ends for conveying balls to the central portion of the ball trough.
7. In a ball receiving and projecting system as recited in claim 5, the gable roof ball shed being inclined rearwardly and having a rear flange upstanding thereon.
8. In a ball receiving and projecting system as recited in claim 7, the screen having a lower edge positioned inside the wings of the ball trough and behind the upstanding rear flange of the gable roof ball shed.
9. In a ball receiving and projecting system as recited in claim 7, the outer end of each wing of the ball trough having a cap with an aperture therein, the screen including a frame having a pair of vertical members with a horizontal member detachably connecting the vertical members, the lower ends of the respective vertical members being detachably supported in the apertures in the caps on the outer ends of the wings of the ball trough.
10. In a ball receiving and projecting system as recited in claim 9, the screen including a rectangular net with an elastic grid therethrough, loops of material fixed along each side and the top of the border receiving the vertical members and horizontal member respectively, and means including a strip of material at the bottom of the net detachably affixing the screen to the rear walls of the respective wings of the ball trough.
11. In a ball receiving and projecting system as recited in claim 8, a fastener pivotally connecting each wing of the ball trough with the central portion of the ball trough whereby the wings of the ball trough can be folded upward for storage, said downturned ends of the wings of the ball trough being radially spaced from the pivots a distance adapting them to bear on the ends of the central portion of the trough, thereby holding the wings of the ball trough in said position inclined toward the central portion of the trough when in position for use.
1. In a ball receiving and projecting system having a ball projector, a ball chute running past the ball projector for feeding balls to be projected and for directing balls projected, a ball trough having front and rear walls and ends, including a pair of wings inclined to a central trough portion having rearward opening for feeding balls to the ball chute, a screen positioned above the ball trough for deflecting balls downward into the ball trough, and a support for the system, the improvement comprising: means for selectively receiving balls alternately from the respective ball trough wings and for ejecting balls in the order selectively received at uniform intervals through said rearward opening into the ball chute, including a disk positioned with the axis thereof parallel with the ball trough and the circumference adjacent the middle of the rearward opening in the ball trough, a semi-circular-section inclined trough member fixed in co-axial spacing around the bottom of the disk and extending upwardly to a position proximate the bottom of the rearward opening in the ball trough, a shaft affixed to the disk along the disk axis, a motor, means connecting the motor for rotation of the disk about the shaft, said motor arranged to rotate in a direction causing the periphery of the disk to move in the upward direction in passing the rearward opening in the ball trough, and first and second lobes on the respective first and second sides of the disk, each said lobe extending from the axis of the disk toward the periphery of the disk in a direction opposite to the extension of the other said lobe.
2. In a ball receiving and projecting system as recited in claim 1, each said lobe defining a surface having a curvature radially of the axis in a direction contrary to the direction of disk rotation and having a width extending in a direction substantially parallel with the disk axis, thereby defining a radially convex ball-urging surface.
3. In a ball receiving and projecting system as recited in claim 2, each radially convex ball-urging surface having a radially extending groove therein, for thereby centering balls on the ball urging surface.
4. In a ball receiving and projecting system as recited in claim 3, the transverse-section shape of each wing of the ball trough comprising a "Y" section with the lower portion thereof being proportioned to prevent any balls which may be received therein from lying side-by-side thereacross, thereby insuring tandem delivery of balls through each respective wing of the ball trough.
5. In a ball receiving and projecting system as recited in claim 4, a gable roof ball shed positioned over the central portion of the ball trough, with a side of the roof sloping downward toward each wing of the ball trough, thereby providing for shunting balls into the trough which might otherwise enter the top of the means for receiving balls from the trough.
6. In a ball receiving and projecting system as recited in claim 5, the central portion of the ball trough being lower than the wings of the ball trough and the wings of the ball trough respectively having downturned inner ends for conveying balls to the central portion of the ball trough.
7. In a ball receiving and projecting system as recited in claim 5, the gable roof ball shed being inclined rearwardly and having a rear flange upstanding thereon.
8. In a ball receiving and projecting system as recited in claim 7, the screen having a lower edge positioned inside the wings of the ball trough and behind the upstanding rear flange of the gable roof ball shed.
9. In a ball receiving and projecting system as recited in claim 7, the outer end of each wing of the ball trough having a cap with an aperture therein, the screen including a frame having a pair of vertical members with a horizontal member detachably connecting the vertical members, the lower ends of the respective vertical members being detachably supported in the apertures in the caps on the outer ends of the wings of the ball trough.
10. In a ball receiving and projecting system as recited in claim 9, the screen including a rectangular net with an elastic grid therethrough, loops of material fixed along each side and the top of the border receiving the vertical members and horizontal member respectively, and means including a strip of material at the bottom of the net detachably affixing the screen to the rear walls of the respective wings of the ball trough.
11. In a ball receiving and projecting system as recited in claim 8, a fastener pivotally connecting each wing of the ball trough with the central portion of the ball trough whereby the wings of the ball trough can be folded upward for storage, said downturned ends of the wings of the ball trough being radially spaced from the pivots a distance adapting them to bear on the ends of the central portion of the trough, thereby holding the wings of the ball trough in said position inclined toward the central portion of the trough when in position for use.
Description:
Cross reference is made to my co-pending application Ser. No. 091,455, filed Nov. 20, 1970 now U.S. Pat. No. 3,713,658, and entitled "Ball Throwing and Receiving System," which has received Notice Of Allowance and for which the Base Issue Fee has been paid; and to my co-pending application Ser. No. 173,798, filed Aug. 23, 1971 (now U.S. Pat. No. 3,761,085) and entitled "Table Tennis Practice & Game Equipment."
This invention relates generally to recreation equipment and specifically to ball receiving and returning apparatus such as that disclosed in my above-referenced co-pending applications.
In the prior art one of the problems not satisfactorily addressed was that of providing a positive-feed metering device to insure that table tennis balls and the like received at random from trough sections extending in opposite directions would be metered out one-by-one to the ball projector without jamming. The problem is easier to solve when the balls are received from a single direction. However, to insure shortest ball-collection time (fastest reaction time) together with most compact dimensions, table tennis equipment of the type described is best equipped with a central projector receiving balls from wing troughs extending to both sides of the projector, as will be further described.
In double-wing devices of this nature a further problem is to prevent a ball metering device from receiving balls from one side in preference to the other side.
A principle object of the invention therefore is to provide a ball receiving and projecting system having a non-jamming ball metering device.
Another object is to provide a metering device as described which receives balls alternately from two directions and which meters the balls received one at a time, and at equal intervals, to a ball projector.
A further object of the invention is to provide co-acting Y-section and U-section trough construction adapted to prevent jamming of balls in the trough.
Still a further object is to provide a ball-shedding gable-roof structure in a central portion of the trough area to prevent ball mis-feeding and jamming.
And yet a further object is to provide a system as described which has simplified, economical, reliable, durable and attractive screen and articulating structure.
In brief summary, a typical embodiment of the invention includes a ball receiving and projection system having a pair of opposed trough wings receiving balls from a screen, co-acting Y-section and U-section trough portions, a ball metering device for receiving one ball at a time from each of the opposed troughs and alternately ejecting first a ball from one trough and then from the other, and novel ball shedding, screening, and articulated structures.
The above and other advantages and objects of the invention will become more readily apparent on examination of the following description, including the figures in which like reference numerals designate like parts:
FIG. 1 is an isometric front view of a preferred embodiment of the invention;
FIG. 2 is a fragmentary isometric detail of a rear portion of the FIG. 1 structure;
FIG. 3 is an isometric front detail, partially broken away;
FIG. 4 is a sectional view taken at 4--4, FIG. 3;
FIG. 5 is a diagrammatic side elevation adapted from 5--5, FIG. 2;
FIG. 6 is a diagrammatic isometric front detail indicating ball channeling by a portion of the structure as viewed in FIGS. 1 and 3;
FIG. 7 is an isometric front view of a screen;
FIG. 7a is an enlarged side elevation detail taken at 7a-7a, FIG. 7; and
FIG. 8 is an isometric front detail of the FIG. 7 construction.
FIG. 1 indicates the front aspects of the invention 10 generally. Supporting legs 12 are shortened for exposition. Each leg is preferably equipped with a rubber cap 14 and the legs are preferably of a length to position the near or front wall 16 of the generally horizontal trough assembly 18 adjacent the lower edge of a standard-height table tennis table, (not shown) with which the unit 10 is adapted for use.
In operation, balls driven by a player practicing table tennis against screen assembly 20, or balls rolled off the end of a table tennis table, are collected by one of the wings 22, 24 of the trough assembly 18. Balls which fall onto the gable-roof 26 over the center portion 28 of the trough assembly 18 are shed into one or the other of the wings 22, 24. The wings are inclined toward the central portion 28 of the trough. Balls channeled to the central portion of the trough are received by a metering device represented by disk 30 and ejected one at a time through a ball feed opening 32 (dotted lines) leading through the rear wall 34 of the trough assembly. Behind the rear wall a ball projector represented by eccentric flexible disks 36, 38 (dotted lines) accelerates the balls. After acceleration the balls follow an upwardly arcuate ball run represented by ball projector chute 40 which protrudes through aperture 42 in the center of the screen or frame-and-netting assembly 20, and are projected back toward the player within an arc defined by the divergent sides 46 and 48 of the ball projector chute 40.
The walls of the trough wings 22, 24 are similarly pivoted to the central portion 28 of the trough assembly as by bolts 50, 52 through the back and front walls respectively. When the gable roof 26 which is laid in place over the central section and secured in place on the central portion by clip 54 fixed to an eave of the gable roof, is removed, and when the screen assembly 20 and ball projector chute 40 are removed, the trough wings 22 and 24 can be folded to a straight-up position for storage. In the working position shown, downturned ends 54 (opposite end not visible) of the trough wings contact the ends of the trough center section 28 and prevent further downward rotation of the wings.
End caps 58, 60 close the outer ends of the respective wings 22, 24 and support the vertical frame members 62, 64, which support the top frame member 66 and together with it hand and stretch the netting 68 of screen assembly 20.
FIG. 2 shows further details of the FIG. 1 arrangement, as viewed from a rear quarter with the trough wings, screen assembly, and ball projector chute removed, leaving the supporting legs 12, projector assembly 70 trough central portion 28 and ball metering assembly 72 assembled together.
The ball projector assembly 70 has a box-like housing comprising a base 74 with three spuds 76 extending downward, a front wall 78 supporting the trough center section 28 by bolts 80; spaced rear walls 82, 84 with the space 86 between for receiving the lower end 88 of the ball projector chute 40 which is secured in place by a screw 90 which passes through hole 92 in rear wall 84 and engages threaded hole 94 in the chute; and side walls 96 and 98. Side wall 98 mounts a motor 100 by means of bolts 102.
The motor shaft 104 extends through a hole 106 in the side wall and mounts and continuously revolves a pair of eccentric flexible disks 36, 38 of rubber or other suitable material.
An arcuate ball run 108 co-axial with the motor shaft 104 is spaced from the shaft a distance causing balls admitted to the ball run 108 through opening 32 to drop under the flexible disks and wedge against them sufficiently to be resiliently grasped between them and violently accelerated rearwardly and upwardly as the flexible disks are revolved in the direction indicated by the arrow by the motor. After acceleration the balls proceed up and around the ball projector chute 40 and are projected from it in a forward direction.
The ball projector chute 40 and the ball run 108 comprise a single continuous ball run or ball chute.
Both the ball projector chute 40 and the legs 12 disassemble from the ball projector assembly for storage, the legs 12 being removed after cotter keys 110 (one shown) are removed from aligned holes 112, 114 in the legs and spuds respectively.
FIGS. 2, 3, 4 and 5 taken together best illustrate the ball metering arrangement of this invention by which balls are delivered one at a time from alternate wings of the trough to the ball projector assembly just described.
The central portion 28 of the trough assembly is generally U-shaped in section, with a raised floor portion 116. The raised floor portion tips downward toward the center from each end and the sides and is semi-circular in transverse section. A tab 118 upturned from the end 120 of the U-section can be used to secure the raised portion 116 in place. The rearward edge of the raised portion 116 rises almost to the lower edge of the opening 32.
The ball metering assembly 72 comprises a motor driven disk 30 having a curved lobe 122, 124 affixed radially to each respective face 126, 128 of the disk. The lobes are fixed in opposite directions on the disk so that they form an "S" curve in side view. The width of each lobe extends in a direction substantially parallel with the disk axis. The disk 30 and the motor drive 130 are mounted in the trough on a pair of horizontal, spaced brackets 132 and 134 (132 shown in FIG. 4) in such position that the plane of rotation of the disk 30 bisects the ball feed opening 32 leading to the ball projector assembly 70. The outer edge of the disk 30 and the outer ends of the radial lobes 122, 124 sweep through an arc just clearing the semi-circular raised portion 116 of the trough. Motor shaft 135 to which the disk is secured by set screws 137 rotatably mounts the disk.
Rotation of the disk is clockwise in FIGS. 2, 3 and 5. The lobes 122, 124 curve reversely or in a retrograde direction with respect to the direction of rotation. Effective width of the trough U-section is made substantially less than two ball-diameters.
In operation, as balls B roll to the center from the ends of the trough they come to rest against the respective faces of the disk 30 so that a ball is picked up from one side of the disk and ejected by a lobe through the opening 32 high on the rear wall and next a ball is picked up from the opposite side of the disk and ejected by a lobe, causing regular-interval projection of balls selected alternately from the two wings of the trough.
FIGS. 3-5 indicate a further important feature of the ball-urging lobes 122, 124 on disk 30 of the ball metering assembly. In addition to being curved radially in a direction contrary to the direction of rotation, making the ball urging surface convex, each convex surface has a radial groove 136, 138 along the middle. Balls being urged by the lobes are first contacted by this grooved surface and follow the groove as they are thrust radially outward and upward. The combination of convex curvature of the surface with the groove insures that balls will not be trapped on the lobes and will not fall off as lifted.
FIGS. 5 and 6 show further details of features of the invention. As in FIG. 5, a ball projector cover 140 is preferably laid over, attached to, or integrally made a part of the ball projector assembly. As in FIGS. 5 and 6, the gable-roof ball shed 26 preferably slants to the rear, and has both an outer flange 142 at the rear to guide balls to the trough wings 22 and 24 (FIG. 6) and a forward inner flange 144 spaced from outer downturned flange 56 so as to grip the center section or central portion 28 of the trough assembly. Outer flange 142 of the gable roof ball shed 26 lies ahead of the screen 20 (FIG. 5) on assembly and prevents ball hang-up also. FIG. 6 shows also the Y-shaped ball-gathering section of the wings 22 and 24 which is broad at the top for gathering and narrow at the bottom to prevent two balls from lying side-by-side, insuring tandem delivery to the central portion of the trough. The combination of the double-slanted ball shed structure over the ball metering section and the uniquely shaped trough sections makes jamming substantially impossible.
FIGS. 7, 7a and 8 detail aspects of the screen assembly 20. The vertical frame members 62, 64 are tubing and slip-fit into angle fittings 146 at the tops which are affixed to the ends of the horizontal or top frame member 66.
Member 66 preferably has a slip-joint 148, 148' in the center permitting disassembly into half lengths, slipping free of the looped top border 150 of the net. The vertical frame members are preferably permanently secured to the lateral net borders 152, 154. The netting 68 is preferably held at an intermediate drape between slack and taut by elastic strips 156 woven through the netting at spaced intervals. The stretch of the elastic strips vertically is achieved by fastening lower net border 158 inside the back walls 34 of the trough wings using snap fasteners. FIG. 7a shows crimping attachment of the snap fastener structure 160 to the lower net border and machine screw and nut fastening 162 of the mating snap fastener structure 160' to the trough wings.
Materials of the invention are preferably one piece transparent plastic such as an acrylic or a polystyrene for the ball projector assembly, the gable roof ball shed, the ball metering disk, and the ball projector chute, each of which is preferably moulded in one piece. Ideally, the central section of the trough assembly would be molded as a part of the ball projector assembly. The flexible disks of the ball projector assembly are preferably of rubber which may be of a moderately elastic grade about 1/16 inch thick. Except for the fabric borders and other limp net portions, the remainder of the invention is preferably of light gauge aluminum.
Obviously many modifications and variations of the present invention are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.
This invention relates generally to recreation equipment and specifically to ball receiving and returning apparatus such as that disclosed in my above-referenced co-pending applications.
In the prior art one of the problems not satisfactorily addressed was that of providing a positive-feed metering device to insure that table tennis balls and the like received at random from trough sections extending in opposite directions would be metered out one-by-one to the ball projector without jamming. The problem is easier to solve when the balls are received from a single direction. However, to insure shortest ball-collection time (fastest reaction time) together with most compact dimensions, table tennis equipment of the type described is best equipped with a central projector receiving balls from wing troughs extending to both sides of the projector, as will be further described.
In double-wing devices of this nature a further problem is to prevent a ball metering device from receiving balls from one side in preference to the other side.
A principle object of the invention therefore is to provide a ball receiving and projecting system having a non-jamming ball metering device.
Another object is to provide a metering device as described which receives balls alternately from two directions and which meters the balls received one at a time, and at equal intervals, to a ball projector.
A further object of the invention is to provide co-acting Y-section and U-section trough construction adapted to prevent jamming of balls in the trough.
Still a further object is to provide a ball-shedding gable-roof structure in a central portion of the trough area to prevent ball mis-feeding and jamming.
And yet a further object is to provide a system as described which has simplified, economical, reliable, durable and attractive screen and articulating structure.
In brief summary, a typical embodiment of the invention includes a ball receiving and projection system having a pair of opposed trough wings receiving balls from a screen, co-acting Y-section and U-section trough portions, a ball metering device for receiving one ball at a time from each of the opposed troughs and alternately ejecting first a ball from one trough and then from the other, and novel ball shedding, screening, and articulated structures.
The above and other advantages and objects of the invention will become more readily apparent on examination of the following description, including the figures in which like reference numerals designate like parts:
FIG. 1 is an isometric front view of a preferred embodiment of the invention;
FIG. 2 is a fragmentary isometric detail of a rear portion of the FIG. 1 structure;
FIG. 3 is an isometric front detail, partially broken away;
FIG. 4 is a sectional view taken at 4--4, FIG. 3;
FIG. 5 is a diagrammatic side elevation adapted from 5--5, FIG. 2;
FIG. 6 is a diagrammatic isometric front detail indicating ball channeling by a portion of the structure as viewed in FIGS. 1 and 3;
FIG. 7 is an isometric front view of a screen;
FIG. 7a is an enlarged side elevation detail taken at 7a-7a, FIG. 7; and
FIG. 8 is an isometric front detail of the FIG. 7 construction.
FIG. 1 indicates the front aspects of the invention 10 generally. Supporting legs 12 are shortened for exposition. Each leg is preferably equipped with a rubber cap 14 and the legs are preferably of a length to position the near or front wall 16 of the generally horizontal trough assembly 18 adjacent the lower edge of a standard-height table tennis table, (not shown) with which the unit 10 is adapted for use.
In operation, balls driven by a player practicing table tennis against screen assembly 20, or balls rolled off the end of a table tennis table, are collected by one of the wings 22, 24 of the trough assembly 18. Balls which fall onto the gable-roof 26 over the center portion 28 of the trough assembly 18 are shed into one or the other of the wings 22, 24. The wings are inclined toward the central portion 28 of the trough. Balls channeled to the central portion of the trough are received by a metering device represented by disk 30 and ejected one at a time through a ball feed opening 32 (dotted lines) leading through the rear wall 34 of the trough assembly. Behind the rear wall a ball projector represented by eccentric flexible disks 36, 38 (dotted lines) accelerates the balls. After acceleration the balls follow an upwardly arcuate ball run represented by ball projector chute 40 which protrudes through aperture 42 in the center of the screen or frame-and-netting assembly 20, and are projected back toward the player within an arc defined by the divergent sides 46 and 48 of the ball projector chute 40.
The walls of the trough wings 22, 24 are similarly pivoted to the central portion 28 of the trough assembly as by bolts 50, 52 through the back and front walls respectively. When the gable roof 26 which is laid in place over the central section and secured in place on the central portion by clip 54 fixed to an eave of the gable roof, is removed, and when the screen assembly 20 and ball projector chute 40 are removed, the trough wings 22 and 24 can be folded to a straight-up position for storage. In the working position shown, downturned ends 54 (opposite end not visible) of the trough wings contact the ends of the trough center section 28 and prevent further downward rotation of the wings.
End caps 58, 60 close the outer ends of the respective wings 22, 24 and support the vertical frame members 62, 64, which support the top frame member 66 and together with it hand and stretch the netting 68 of screen assembly 20.
FIG. 2 shows further details of the FIG. 1 arrangement, as viewed from a rear quarter with the trough wings, screen assembly, and ball projector chute removed, leaving the supporting legs 12, projector assembly 70 trough central portion 28 and ball metering assembly 72 assembled together.
The ball projector assembly 70 has a box-like housing comprising a base 74 with three spuds 76 extending downward, a front wall 78 supporting the trough center section 28 by bolts 80; spaced rear walls 82, 84 with the space 86 between for receiving the lower end 88 of the ball projector chute 40 which is secured in place by a screw 90 which passes through hole 92 in rear wall 84 and engages threaded hole 94 in the chute; and side walls 96 and 98. Side wall 98 mounts a motor 100 by means of bolts 102.
The motor shaft 104 extends through a hole 106 in the side wall and mounts and continuously revolves a pair of eccentric flexible disks 36, 38 of rubber or other suitable material.
An arcuate ball run 108 co-axial with the motor shaft 104 is spaced from the shaft a distance causing balls admitted to the ball run 108 through opening 32 to drop under the flexible disks and wedge against them sufficiently to be resiliently grasped between them and violently accelerated rearwardly and upwardly as the flexible disks are revolved in the direction indicated by the arrow by the motor. After acceleration the balls proceed up and around the ball projector chute 40 and are projected from it in a forward direction.
The ball projector chute 40 and the ball run 108 comprise a single continuous ball run or ball chute.
Both the ball projector chute 40 and the legs 12 disassemble from the ball projector assembly for storage, the legs 12 being removed after cotter keys 110 (one shown) are removed from aligned holes 112, 114 in the legs and spuds respectively.
FIGS. 2, 3, 4 and 5 taken together best illustrate the ball metering arrangement of this invention by which balls are delivered one at a time from alternate wings of the trough to the ball projector assembly just described.
The central portion 28 of the trough assembly is generally U-shaped in section, with a raised floor portion 116. The raised floor portion tips downward toward the center from each end and the sides and is semi-circular in transverse section. A tab 118 upturned from the end 120 of the U-section can be used to secure the raised portion 116 in place. The rearward edge of the raised portion 116 rises almost to the lower edge of the opening 32.
The ball metering assembly 72 comprises a motor driven disk 30 having a curved lobe 122, 124 affixed radially to each respective face 126, 128 of the disk. The lobes are fixed in opposite directions on the disk so that they form an "S" curve in side view. The width of each lobe extends in a direction substantially parallel with the disk axis. The disk 30 and the motor drive 130 are mounted in the trough on a pair of horizontal, spaced brackets 132 and 134 (132 shown in FIG. 4) in such position that the plane of rotation of the disk 30 bisects the ball feed opening 32 leading to the ball projector assembly 70. The outer edge of the disk 30 and the outer ends of the radial lobes 122, 124 sweep through an arc just clearing the semi-circular raised portion 116 of the trough. Motor shaft 135 to which the disk is secured by set screws 137 rotatably mounts the disk.
Rotation of the disk is clockwise in FIGS. 2, 3 and 5. The lobes 122, 124 curve reversely or in a retrograde direction with respect to the direction of rotation. Effective width of the trough U-section is made substantially less than two ball-diameters.
In operation, as balls B roll to the center from the ends of the trough they come to rest against the respective faces of the disk 30 so that a ball is picked up from one side of the disk and ejected by a lobe through the opening 32 high on the rear wall and next a ball is picked up from the opposite side of the disk and ejected by a lobe, causing regular-interval projection of balls selected alternately from the two wings of the trough.
FIGS. 3-5 indicate a further important feature of the ball-urging lobes 122, 124 on disk 30 of the ball metering assembly. In addition to being curved radially in a direction contrary to the direction of rotation, making the ball urging surface convex, each convex surface has a radial groove 136, 138 along the middle. Balls being urged by the lobes are first contacted by this grooved surface and follow the groove as they are thrust radially outward and upward. The combination of convex curvature of the surface with the groove insures that balls will not be trapped on the lobes and will not fall off as lifted.
FIGS. 5 and 6 show further details of features of the invention. As in FIG. 5, a ball projector cover 140 is preferably laid over, attached to, or integrally made a part of the ball projector assembly. As in FIGS. 5 and 6, the gable-roof ball shed 26 preferably slants to the rear, and has both an outer flange 142 at the rear to guide balls to the trough wings 22 and 24 (FIG. 6) and a forward inner flange 144 spaced from outer downturned flange 56 so as to grip the center section or central portion 28 of the trough assembly. Outer flange 142 of the gable roof ball shed 26 lies ahead of the screen 20 (FIG. 5) on assembly and prevents ball hang-up also. FIG. 6 shows also the Y-shaped ball-gathering section of the wings 22 and 24 which is broad at the top for gathering and narrow at the bottom to prevent two balls from lying side-by-side, insuring tandem delivery to the central portion of the trough. The combination of the double-slanted ball shed structure over the ball metering section and the uniquely shaped trough sections makes jamming substantially impossible.
FIGS. 7, 7a and 8 detail aspects of the screen assembly 20. The vertical frame members 62, 64 are tubing and slip-fit into angle fittings 146 at the tops which are affixed to the ends of the horizontal or top frame member 66.
Member 66 preferably has a slip-joint 148, 148' in the center permitting disassembly into half lengths, slipping free of the looped top border 150 of the net. The vertical frame members are preferably permanently secured to the lateral net borders 152, 154. The netting 68 is preferably held at an intermediate drape between slack and taut by elastic strips 156 woven through the netting at spaced intervals. The stretch of the elastic strips vertically is achieved by fastening lower net border 158 inside the back walls 34 of the trough wings using snap fasteners. FIG. 7a shows crimping attachment of the snap fastener structure 160 to the lower net border and machine screw and nut fastening 162 of the mating snap fastener structure 160' to the trough wings.
Materials of the invention are preferably one piece transparent plastic such as an acrylic or a polystyrene for the ball projector assembly, the gable roof ball shed, the ball metering disk, and the ball projector chute, each of which is preferably moulded in one piece. Ideally, the central section of the trough assembly would be molded as a part of the ball projector assembly. The flexible disks of the ball projector assembly are preferably of rubber which may be of a moderately elastic grade about 1/16 inch thick. Except for the fabric borders and other limp net portions, the remainder of the invention is preferably of light gauge aluminum.
Obviously many modifications and variations of the present invention are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.