US2199009A - Table tennis player - Google Patents

Description

April 1940- G. H. PERRYMAN 2,199,009

TABLE TENNIS PLAYER Filed Sept. 27, 1938 3 Sheets-Sheet 2 raEE g a f F INVTOR eorgedv. err 'yman/ April 39, 1940. G H, P R Y AN 2,199,009

TABLE TENNIS PLAYER Filed Sept. 27, 1958 3 Sheets-Sheet 3 will IIIIIIIIIII eorggefl Per-r rnan/ Y Patented Apr. 30, 1940 UNITED STATES PATENT OFFICE 10 Claims.

This invention relates to a device for use in playing or practicing the game of table tennis or any similar game wherein a ball is propelled toward a player to be batted or struck by him, and has for its object the provision of a device which will propel successive table tennis or other balls across a playing table toward one or more players located at one end thereof, to enable the players to strike or bat the ball so propelled and thus gain skill in playing the game. The improved device also enables one person to play or practice the game.

A further object of the invention is to provide a device of this character in which the propulsion of successive balls will be continuous, as long as the player desires to continue the play. That is to say, by initially setting the device in operation, balls will be successively propelled or ejected across the playing net toward the player, and when the balls are struck by the player, they will be directed into a return guide which will deliver them to the propelling device through which they will again pass and be projected over and over again to the player.

Another object of the invention is to provide means by which the balls propelled from the playing device will be given a rotative movement or spin similar to that often imparted to the ball by skilled players in an effort to make the return blow by the opposing player difiicult.

Another object of the invention is to provide means by which the spin-creating mechanism will be automatically variable so that the direction of spin of each successive ball will be difierent to a greater or lesser extent, or in a dilierent direction, from that of the ball which preceded it through the playing device.

Another object of the invention is the provision of means by which operation of the device will be wholly automatic so that by the closing of a switch, the device will be set in operation and will continue in operation until the switch is opened by the player.

In the accompanying drawings, wherein an embodiment of the invention is shown, Fig. 1 is a plan View of a tennis table showing the playing device stationed at one end of the same; Fig. 2 is a sectional View on the line 22 of Fig. 1, looking in the direction of the arrows; Fig. 3 is a side elevation of the ejection tube, showing the mechanism for automatically imparting rotary movement to the ball spinner; Fig. 4 is a plan view of the structure shown in Fig. 3 with parts in section and other parts broken away to disclose construction; Fig. 5 is a side elevation, with parts in section, of a modified structure showing a hand-operated plunger for ejecting the balls from the ejection tube; Fig. 6 is a side elevation, with parts in section, of the structure disclosed in Figs. 1 to 4 inclusive; Fig. 7 is a sectional view of the ball spinner; Fig. 8 is a sectional view on the line 58 of Fig. 7, looking in the direction of the arrows; Fig. 9 is a sectional view on the line 99 of Fig. 8, looking in the direction of the arrows; Fig. 10 is a sectional view similar to that of Fig. 8 showing how the flexible ball spinning member may be adjusted; Fig. 11 is a side elevation, partly in section, of a structure in which a modified type of electro-magnet is employed for retracting the plunger, and for elevating successive balls through the feed tube; Fig. 12 is a sectional view on the line Ill-l2 of Fig. 11, looking in the direction of the arrows; and Fig. 13 is a sectional View on the line Iii-l3 of Fig. 11, look ing in the direction of the arrows.

In the embodiment of the invention shown in Figs. 1 to 4 inclusive, and Figs. 6 to 10 inclusive, a tennis table of conventional construction is indicated at I, the same being provided with the usual top 2 and supporting legs 3. The table is of usual construction and forms no part of the present invention. Stretched across the table in the conventional manner is the net 4 which may form a part of the playing device or may be the conventional kind employed in the game of table tennis. One or more players engaging in play will be positioned at the end of the table shown at the right of Fig. 1.

The playing device includes a ball-collection structure enclosed at three sides by either upstanding or inclined walls 5, 6 and 'l which may be composed of fabric netting or the like, and against which balls batted by the player will strike and fall down on the inclined bases 8 and 9. The balls 35 striking the bases 8 and 9 will be guided by gravity into a central feed channel [0 in which they will successively roll downwardly, as indicated in Fig. '6, into an entrance opening ll formed in a housing 12. The housing I2 is adapted to be clamped over the edge of the table top 2, as shown in Figs. 2 and 6, at a position opposite to the player, said housing having a lower flange I3 into which one or more set screws I4 extend to securely, yet detachably, hold the device on the end of the table.

Secured in the upper end of the housing I? and extending upwardly therefrom is a sleeve or nipple 15, on which is fitted and from which extends, a flexible, non-collapsible feed tube l6 through which the balls are successively fed upwardly to reach the ejection head I8 to which the upper end of the flexible feed tube It is attached through the medium of a sleeve or nipple IS. The head i8 is adjustably supported from housing l2 by means of a rod 29 which has its lower end rotatively fixed in the housing l2 by means of the set-screw 2i engaging an annular groove in the rod, and its upper end pivotally attached at 22 in a clevis 23 formed on the ejection head H3.

The balls entering the chamber l2 are successively forced upwardly through feed tube l6 by means of the armature 24 of an electro-magnet located in a receptacle 24a and extending downward below the housing I2. The winding 25 of the electro-magnet is connected by the leads 26 and 2! to a source of current such as the usual house lighting current diagrammatically indicated at 28.

Connected in the circuit is a normally-closed thermostatic switch 29 and a manually operated switch 39. The electrical connection of the parts described is such that when switch 3!) is manually closed, the thermostatic switch 29 being at that time also closed, the armature 24 will be moved upwardly and will force a ball upwardly in the feed tube IS. The wall of the sleeve or nipple I is slotted at 3| and operative through said slot is a ball-retaining spring 32, which prevents the balls in the tube from falling down by gravity. When the thermostatic switch 29 becomes heated and opens, the armature 24 will drop down by gravity so that another ball may roll through entrance II to position above the armature in readiness to be lifted up into the tube I6 by the next upward movement of the armature.

Mounted in the ejection head I8 is a plungercontaining tube 33 within which the plunger 34 is adapted to be reciprocated, the plunger under spring propulsion in one direction acting to project one of the balls 35 after another out of the open end of the ejection head [8. The tube 33 extends rearwardly from the head l8 and plunger 34 is in the form of an armature movable through the winding 36 under magnetic attraction when the winding is energized through its connecting leads 31 and 38 extending to the source of current 28.

Extending rearwardly from the plunger 34 and secured to or forming a part thereof is a rod 39 surrounded by a spring 40 which normally tends to maintain the plunger 34 at the limit of its forward movement or in its projected position, as shown in Fig. 6. One end of said spring is operative against the shoulder 4| on the plunger, and the other end bears against an adjustable bushing 42 threaded through the closure member 43 located in the end of sleeve 33. At the outer end of the rod 39 is provided a bumper 44 which may be of rubber or the like, to resiliently limit the projected movement of the plunger 34 toward the right, as viewed in Fig. 6, under the propulsion of the spring 40. The adjusting bushing 42 may be regulated through the head 43 to govern the length of stroke of the plunger 34 and to accordingly govern the speed of the balls projected by the plunger.

, When the manually-operated switch 30 is closed, the thermostatic switch 29 being normally closed, the circuit to the winding 36 will be closed, and the winding will be energized to magnetically draw the plunger 34 within it and toward the left as viewed in Fig. 6, against the tension of spring 40. As plunger 34 is being so retracted, armature 24 is being simultaneously raised and it forces a ball up into the feed tube [6. The ball indicated at 35a, or that next to be ejected by the plunger, and shown supported by the plunger 34, will, when the plunger is so retracted, fall down into the passage extending through the ejection head 18 and be then located directly in the path of the plunger. Thus, when the thermostatic switch 29 becomes heated and snaps to off position to break the circuit, the winding 36 will no longer be energized and spring 40 will at once project the plunger 34 toward the right, causing it to strike the ball 35a then positioned in its path and forcibly project it out of the open end of a sleeve 45 which is located at the end of the ejection head 18. As the thermostatic switch snaps off and on with its heating and cooling, successive balls will be projected out of sleeve 45 by the operation of the plunger with a short time lapse between the ejection of each ball and that which is next struck by the plunger so that a player stationed at the right end of the table will have ample tme to strike a ball propelled toward him and bat it into the enclosure located around the device before the next ball is projected toward him.

The means for imparting a spin or rotative movement to the ball while in flight from the playing device toward the player is shown in detail in Figs. 3, 4 and 7 to inclusive. The sleeve 45 is located within a rotative bushing 46 formed with an annular groove 4'! engaged by the screw 48, which holds bushing 46 within the end of the ejection head 18 and permits it to be rotated, yet holds it against axial movement. The inner end of bushing 46 is cut away, as indicated at 49, for a portion of its circumference and the inner sleeve 45 is somewhat similarly cut away as indicated at 50. Since this inner sleeve 45 may be rotated, preferably with a slight amount of frictional resistance, within the bushing 46, the cutaway portions 43 and 55 of the bushing and sleeve respectively, can either be aligned or disposed in registration with one another, as indicated in Fig. 8, or else disaligned to any required extent, an example of which is shown in Fig. 10. The rotative movement of the sleeve 45 within the bushing 46 is restricted by a radially projecting pin 5| extending from the face of sleeve 45 and adapted to strike against one or the other of the ends of the cut-out portion 43 when the limits of rotative movement of the sleeve 45 within the bushing 46 are reached.

Extending around the concentrically disposed portions of the sleeve 45 and bushing 46 within the chamber 52 of the ejection head [8, is a rubber band 53 or similar elastic member.

sleeve 45 and bushing 46 is such that a portion of the band is stretched straight across the cut-out portions 49 and 5!! of the sleeve and bushing, as indicated at 54 in Figs. 7 and 8. This portion 54 of the rubber band acts as a resilient resisting element which frictionally operates against the periphery of a ball that is thrust past it by the plunger 34, causing a spin to be imparted to the ball, as the ball is projected out of the sleeve 45 by the operation of the plunger 34. The degree of resistance exerted by the portion 54 of the band on the ball is dependent upon the extent of projection of said portion 54 within the passage through which the ball is forced by the plunger. Thus, in Fig. 8, the portion 54 of the band extends to a maximum extent across the path of the ball because the cut- away portions 49 and 50 of the bushing and sleeve 46 and 45 are in full registration. When the sleeve 45 is manually The disposition of the rubber band 53 around the rotated slightly within the bushing 45, the part 54 of the band is reduced in;length and the extent of its projection in the path of the ball will also be decreased. This will be clear. from Fig. 10.

It is possible to make the band wholly inopera-- tive on the ball by rotating sleeve 45 for the maximum extent in a clockwise direction, as viewed in Fig. 10, so that the cutaway portion 55 will be completely disaligned with the cutaway portion 49 and there will then be no opening through which any portion of the band may project into the interior of the ballpassage. Thus, any balls projected out of the device when it is in such a position of adjustment will have only the normal spin of a ball propelled in the conventional way. I

The entire ball-spinning assembly, consisting of the elements 45, 46 and the band 53 is adapted to be rotated with an intermittent movement to shift the position of ball-resisting portion 54 with respect to the ball and thereby vary the direction of spin of the ball, as it emerges from the open end of the sleeve 45. Bushing 46 is provided with a projecting flange 51 which has a face formed with ratchet teeth 58 that are spaced lugs 52 and 63 extending from the side of the ejection head i8, is a rod 64 provided at one end with a cam surface 65 held against the laterally extending end 66 of pawl 59, by means of the spring 61. The opposite end of the rod 1 E4 is located in position to abut against a pawl l5 pivoted at 39 in ears H formed on the tube 53. Pawl has a pivoted, spring-pressed inner end 12 which extends into the tube 33 through aperture 73 therein, said end 12 being normally held by a spring 15 in the path of a head formed or fixed on the forward end of the plunger 34-. Thus, when the plunger 34 is drawn to a retracted position by operation of the electromagnet, the head 14 will impinge against the end E2 of pawl it, causing the opposite end of the pawl to exert a thrust on rod 64. Cam surface 65 on said rod, operative upon the end 56 of pawl 59, will swing the spring-pressed end 6! of said pawl upwardly causing it to move the ratchet and causing the bushing 46 and sleeve 45 to be rotated slightly. Since this rotative movement of the bushing 46 occurs at each retractive movement of the plunger, it is obvious that the ensuing forward thrust of the plunger will force the ball which it propels against the portion 54 of the band, while that portion of the band is located in a position relative to the ball slightly different from its position which it occupied when the previous ball was forced past it. Accordingly, as each ball is projected out of the sleeve 45 by the plunger a somewhat different twist or spin will be imparted to it and the manner in which the successive balls are propelled to the player will thus be varied so that an interesting and active game, played by one or more persons and the playing device, will ensue. I

Briefly, the operation of the device is as follows:

The feed tube 15 is filled with balls and a few additional balls may be disposed in the feed channel W in which they will roll down into the interior of the housing i2. A player, stationed at the right end of the table, will then close switch 3llwhich is preferably located conveniently near him inan extension cord; Thermostatic switch 29 is a normally closed switch and thus, when manually-operated switch is.

16 into the ejection head l8 where it is restrained from falling out by means of the portion 54 of the band 53. When plunger 34 is retracted, arm-- ature 24 is simultaneously elevated so that while one ball drops down into position in readiness to be ejected, another will be moved up into the feed tube by armature 24 into position past the spring 32. When thermostatic switch 29 becomes heated, it will snap to open position, thus breaking the circuit, and plunger 34 will at once be propelled forward under the impulse of the spring 45 and project the ball out of the open end of the sleeve 45 and toward the player stationed on the other side of the net 4, who will bat the ball into the enclosure surrounding the playing device, from whence it will roll down into the feed channel l0. As the ball is projected out of the sleeve 45, its periphery will be frictionally engaged by the portion 54 of the resilient band so that the act of forcing the'ball past the band will cause the'band to impart a spin to the ball similar to that imparted by expert players of this game. The location of. the portion 54 of the band determines the direction of imparted spin, and since each retractive movement of the plunger will by the action of the pawl and ratchet mechanism cause the portion 54 of the band to be shifted to a different position relative to the ball, it is apparent that each ball will be spun in a different manner as it is propelled from the device until a complete cycle has been completed and then a repeat of the spins will occur. By elimination of the pawl and ratchet mechanism for rotating the elastic band mounted or bya-throw-off means for such mechanism, the ball-contacting portion 54 of the band 53 may remain stationary so that the successive balls propelled from the device will have the same applied spin. This is of par-' ticular importance to those players who find difficulty in striking the ball when it is delivered to them at a specified point on the table with a certain spinning action capable of being ap- "plied by skilled players. Thus, such va player :an perfect a particular stroke or correct his playing weaknesses by having ball after ball delivered to him at a certain spot with a uniform spin. The spin-applying means can also be made capable of manual setting and adjustment instead of an automatically changeable one whereby the bushing 46can be manually rotated to any desired position independently of the plunger operation.

As long as balls are kept in circulation through the feed tube, and the manually-controlled switch 30 is maintained in closed position, the device will be kept in operation by the automatic intermittent opening and closing of the thermostatic switch, sothat a player can play steadily for hours at a time if desired with noeifort'on his part other than batting the balls into the enclosure extending around the playing device.

While I have shown electrical means for operating the device, it will be obvious that this struc ture can be embodied in a hand-operated form, an example of which is shown in Fig. 5. There, the solenoid type of plunger, such as shown in Fig. 6, is replaced bya hand-operated plunger.

consisting of a rod 80, having a head 8I provided on its forward end, and a handle 82 at its opposite end. Plunger 80 is reciprocable in the tube 33 by having the handle manually engaged and pulled rearwardly against the tension of the spring 83 and then released. When the grip on the handle 82 is released, spring 83 will thrust the plunger forward and cause it to strike the ball then located in the ejection head I8 and propel it out of the sleeve 45. A stop member 84 is used on plunger 80 and the same impinges against a partition 85 located within the sleeve 33 to thereby limit the movement of the plunger. The ball-spinning means such as previously de- 1 scribed in connection with the structure shown in Figs. 6 to 10 may be employed in connection with such a hand-operated device as is shown in Fig. 5, or a manually-adjustable spinner can be used.

In the modification of the invention shown in Figs. 11 to 13 inclusive, a structure is disclosed which is similar in operation to that previously described, except that it utilizes a different type of electro-magnet for retracting the ball-projecting plunger and also for feeding the balls into the feed tube. The type of magnet there employed for retracting the plunger is one particularly adapted for use in connection with alternating current. It is shown at 89 and includes a twopart frame 90 in which is clamped a plurality of slotted plates 9I, and which encloses the winding 92. The frame 90 may be clamped or otherwise secured on the plunger tube 93 by means of the screws 94 or the like. The upper ends of the two halves of the .frame 90 are formed with cars 95 between which is pivotally mounted at 98 the upper end of the armature 96, the same consisting of a plurality of plates bolted or riveted together and provided with a downwardly projecting stem portion 91, the lower end of said stem portion extending through elongated slots 99 formed in the plunger tube 93. The plunger I00, movable within the tube 93, is slotted at IOI and the lower end of the stem 91 projects into the slot IOI in the plunger. Extending rearwardly from and attached to or forming a part of the plunger I is a stem or rod I02 surrounded by the spring I03 and extending through the adjustable bushing 42 in the end of tube 93. Rod I02 is provided with a bumper 44 or if desired, said bumper. may be located within the body of the tube 93 in a manner somewhat similar to that shown in Fig. 5.

The magnet I employed for lowering the ball-feeding plunger I04 is similar to that shown for the retraction of the plunger I00. The stem 91 of magnet I05 engages in a slot I06 in the plunger I04 and when the magnet I05 is energized, the armature thereof will be drawn downwardly and it will pull the plunger I04 down against the tension of spring I01 located in tube I08 and surrounding the stem portion I09 projecting from the plunger I04. When the circuit to the magnet I05 is broken, spring I01 will force the plunger I04 upwardly to the position shown in Fig. 11, causing the plunger to push one of the balls up into the feed tube IS. A bumper IIO on stem I09 limits upward movement of the plunger I 05 and absorbs shock. When the circult to the magnet 89 is closed, the same will swing the armature 96 toward the left as viewed in Fig. 11, causing the plunger I00 to be drawn to a retracted position. When circuit to magnet 83 is broken, spring I03 will force the plunger I00 forwardly and cause it to eject a ball out through sleeve 45 in the manner previously explained. As the ball-ejecting plunger propels a ball out of the sleeve 45, the ball-feeding plunger I04 forces a ball up in the feed tube under the impulse of spring I01.

The structure is very flexible in use and may be embodied in various shapes and forms to meet different requirements. Due to the flexible, noncollapsible construction of the feed tube I6, the ejection head and connecting parts may be swung from side to side and also inclined or tilted in various positions due also to the pivot joint 22 which can, if desired, be a universal joint. It is thus possible to direct the outlet opening of the sleeve 45 at any point on the table so that it will project the balls either close to or at a substantial distance from the net 4. The speed of spin or rotation of balls ejected from the device can be governed by the inward projection of the portion 54 of the elastic member within tube 45. The force of propulsion of the ball can be regulated by the adjusting member 42 which will govern the throw of the plunger. The direction of spin of the ball is either manually regulatable or automatically variable according to the structure employed, several embodiments of which were herein disclosed.

While I have shown several embodiments of the invention, it is obvious that the same is not to be restricted thereto, but is broad enough to cover all structures coming within the scope of the annexed claims.

What I claim is:

l. A device for playing table tennis or other ball games comprising a holder for a ball to be propelled, means for engaging said ball and projecting the same out of the holder, means for imparting a spin to the ball as it is projected, said means comprising a resilient element stretched across the holder and against which the periphery of the ball is forced by the projecting means and which, by frictional resistance against the periphery of the ball, imparts a rotative movement to the ball as it is projected out of the holder.

2. In a ball-playing device, means for forcibly projecting a ball toward a player, spin-imparting means including a resilient fixed element situated in. the path of movement of the ball as the ball is projected by the projection means, said resilient fixed element being operative against the surface of the ball to rotate the ball as the ball is moved by the projection means, and means controlled by the ball-projecting means for presenting the ball-rotating means in different positions to successive balls projceted.

3. A device for playing table tennis or other ball game comprising, a holder for a ball to be projected toward a player, means for engaging said ball while the same is in the holder and forcing it out of the holder, an elastic element disposed across the holder in the path of the ball being propelled, said element resiliently expanding to permit passage of the ball but applying a frictional resistance against the face of the ball to impart a spin to the ball as the ball is projected out of the holder, and means controlled by movement of the ball-propelling means for presenting the ball-rotating means in different positions to successive balls projected.

4. In a ball propulsion device, a holder for a ball to be propelled, a ball-striker for impinging against the ball and projecting it out of the holder, an elastic strip disposed in the path of the ball to frictionally engage the face of the ball and cause it to spin as it is projected, means for increasing or decreasing the extent of projection of the strip in the path of the ball, and ball-striker controlled means for automatically shifting the position of the strip relative to the periphery of the ball, whereby the strip will be presented to a ball in a position different from that in which it was presented to the preceding ball.

5. A device for playing table tennis comprising a tube having an open end, means for delivering successive balls into the tube near its open end,

a plunger reciprocable within the tube for striking the successive balls and forcibly projecting the same one after another out of the open end of the tube, magnetic means for drawing the plunger in one direction, spring means for forcing the plunger in the opposite direction, means for automatically intermittently operating the magnetic means, and means at the outlet end of the tube for imparting a spin to each ball as it is ejected from the tube by operation of the plunger, and means controlled by the plunger for automatically shifting the position of said spin-imparting means after the ejection of each ball.

6. A table tennis player or the like comprising, a projection tube having an open end, a plunger movable within said tube to project successive ;balls out of the tube, an electro-magnet for drawing said plunger to a retracted position in the tube, spring means for projecting the plunger toward the open end of the tube when the magnet is inoperative, a feed tube communicating with the projection tube and conveying balls thereto, a feed plunger for forcing successive balls through the feed tube toward the ejection tube, magnetic means for withdrawing the feed plunger to non-feeding position, spring means for moving the feed plunger to feeding position, and an intermittently operated switch for controlling the intermittent operation of the magnetic means for both plungers.

7. A table tennis player or the like comprising, a projection tube having an open end, a plunger movable within said tube to push successive balls out of the tube, an electro-magnet for drawing the plunger to a retracted position in the tube, spring means for projecting the plunger toward the open end of the tube when the magnet is inoperative, a feed tube communicating with the projection tube and conveying balls thereto, a feed plunger for forcing successive balls through the feed tube toward the ejection tube, an electro-magnet for withdrawing the feed plunger to non-feeding position, spring means for moving the feed plunger to feeding position when the last-mentioned electro-magnet is inoperative, and means for intermittently rendering both electro-magnets operative.

8. In a table tennis player, a feed tube into which balls are directed, an ejection tube into which balls are delivered by the feed tube, a plunger for ejecting the balls successively out of the feed tube, an electro-magnet for pulling the plunger in one direction, and a spring for pushing it in the opposite direction, means for imparting a spin to each ball as it is propelled out or the ejection tube by the plunger, said spinimparting means comprising an elastic element stretched across the ejection tube at a distance rearwardly of the open end of the tube whereby a spin is imparted to each ball without changing its direction of propulsion.

9. A table tennis player or the like comprising, a feed tube into which balls are directed, an ejection tube into which the balls are directed from the feed tube, a plunger for successively ejecting balls out of the ejection tube, and means in the ejection tube controlled by said plunger for automatically imparting a spin in a different direction to each ball as it is ejected out of the ejection tube.

10. In a ball-playing device, means for forcibly projecting a ball toward a player, said means including a plunger, spin-imparting means including an element fixed in relation to the direction of movement of the ball for frictionally engaging the periphery of the ball as the ball is moved past it and imparting a rotative movement to the ball, and means controlled by the plunger for automatically rotatively shifting the position of said spin-imparting means so that it may be presented at different positions to sue-- cessiv balls to be projected past it.

GEORGE H. PERRYMAN.

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