Background of the Invention
The invention achieves tautness in cable movement while the ball is shortly tethered from the cable slide bushing, features not achieved by the earlier Coffee U.S. Pat. No. 1,554,409, in 1925; or by the Anson U.S. Pat. No. 2,772,882 in 1956. Nor is the cable elastic and stretchable substantially coextensive with ball travel as in the Denegree U.S. Pat. No. 3,042,401, 1962. Nor does the upper end of the cable have to be anchored to a necessarily locatable natural object, with ball return by gravity, as in Albert U.S. Pat. No. 3,086,776, 1963. Also only a single cable is required rather than upper and lower cables, as required by Lingbeck U.S. Pat. No. 3,630,521, 1971. Finally, the invention provides a decided improvement in degree of simulation of actual swinging against the force of a thrown baseball due; the live ball rebounding with force after striking any point of a backboard; such backboard, or ample rebound imparting area not being provided by even the latest Adkins U.S. Pat. No. 3,703,286, 1972.
The invention thus relates to a baseball batting practice device that simulates, (upon ball rebound from backboard, as tether slides back along a studiedly prepositioned cable), the arrival of a thrown baseball in confrontation with a batter, this similarity being attained by a particularly calculated combination of structures.
As a particular object, the invention sets out to provide a baseball batting practice device with all parts assembled with tautness, with batted ball of live, resilient material, tethered by a braided cord to a substantially weightless slide bushing which travels a cable between frames, to stop before a backboard of substantial area, which is struck by the ball which rebounds with substantial force to return to location again to be batted.
It is also an important object of the invention to provide a baseball batting practice device of this class which provides a coil spring cage, with springs in such tension as to yield to any slight deflection of the music wire or cable between frames, as such deflection tends to be caused by the slide bushing, braided cord, tethered ball being struck by a batter with an impact in direction other than directly toward the confronting backboard; upon ball rebound the coil springs restoring the music wire to normal straight axis extension.
It is yet another object of the invention to provide a baseball batting practice device of this class in which the ball, of live resilient material, is tethered by means of a braided, substantially non-stretchable cord to a substantially weightless slide bushing, lined to minimize sliding friction between the bushing and cable.
It is also a further object of the invention to provide a baseball practice device of this class with spring cage and backboard on similarly constructed frames or uprights provided to permit selective adjustment of spring cage and backboard in elevation, the same adjustments being permitted when spring cage assembly and backboard assembly are switched with relation to frames or uprights.
Other and further objects will be apparent when the invention is considered in connection with the drawings, with views to be briefly described immediately hereinbelow, and to be further described at length in the following details of the specification.
Brief Description of the Drawings
FIG. 1 is a side elevational view of an embodiment of a baseball practice apparatus.
FIG. 2 is a plan view taken along line 2--2 of FIG. 1.
FIG. 3 is a transverse sectional elevational view, looking forwardly at the rebounding board of the apparatus.
FIG. 4 is a fragmentary isometric view showing the operation of the tension spring assembly and ball carrier wire.
FIG. 5 is an isometric view of the rebounding board.
FIG. 6 is an enlarged cross-sectional, elevational view showing details of ball anchorage and slide carrier details.
Summary of the Invention
The invention is of a baseball batting practice device which permits the establishment of axis of live resilient ball suspension at adjustable, predetermined elevation, with struck ball to travel as directed, within limits, and with slightest friction along suspension cable axis to strike a backboard of ample area. The live ball rebounds to be returned by force of rebound, as slidable suspended, to original batter swinging position. Upon ball rebound a spring cage opposite the backboard supporting end of the device restores the music wire or cable between support frames, from deflected to a normally straight, predetermined travel axis.
Detailed Description
Referring now to the drawings, in which like reference numerals are applied to like elements in the various views, a baseball batting practice device is shown in FIG. 1 with a spring cage frame or supporting upright 10, to the left, spaced from a backboard assembly frame or supporting upright 11 on the right. A cable or music wire 12 extends between the uprights 10 and 11 with a slide bushing 13 being indicated as slidable thereon, a suspension cord 14 carries the ball 15 suspended below the slide bushing, at elevation above ground or base level best to be struck by a practice batter.
As shown in FIGS. 1 and 2, each frame or upright 10, 11, includes, respectively left and right upright members 15a, 15b, above a transverse angle 16 at bottom, with left and right base runners 17a, 17b, extending rearward and forwardly respectively, and with left and right diagonals 18a, 18b, extending upwardly from the base runner outer ends to be connected upwardly to the respective upright members 15a, 15b. Upper, central and lower transverse members 19a, 19b, 19c extend between, and space apart, the upright members 15a, 15b, while these uprights are side braced by diagonal members 20a, 20b, best shown in FIG. 3, with lower ends connected outwardly to the transverse angle 16 near the outer ends thereof. As shown in FIG. 3, the uprights have equally spaced apart and cross aligned bolt holes therethrough for adjustably disposing spring cage or backboard assembly, (to be described later), at selective, predetermined elevations.
If FIGS. 1, 2 and 3 are now considered with relation to FIG. 4, the construction and operation of the spring cage assembly 21 may best be understood. As hereinabove stated, the spring cage or spring cage assembly, through its tensioned coil springs 22, restores the cable or music wire 12 to a straight axis, if deflected by the blow of a bat striking the ball other than straight forwardly.
The cage assembly 21 comprises rearwardly a rectangular structure 23, including left and right, vertically disposed angles 23a, 23b, connected by upper and lower cross members 23c, 23d. From the angle corners smaller frame angles 24a, 24b, 24c, 24d extend slightly diagonally forwardly to converge at the forward end of the spring cage assembly at tops and bottoms of left and right, vertically disposed angles 25a, 25b, which are shorter than the angles 23a, 23b. A cross plate structure 26 connects the angles 23a, 23b. Coil springs 22 normally in tension, have their rear ends connected, at substantially equally spaced apart locations, to the vertical angles 23a, 23b, and the cross members 23c, 23d. These springs 22 extend forwardly and connect at their forward ends around the top, sides and bottom of a vertically disposed, rectangular plate 27, of dimensions that its corners are spaced inwardly with clearance from the aforesaid frame angles 24a, 24b, 24c and 24d. An anchor bolt 28 is connected through the center of the connection plate 27, with the eyelet end of the anchor bolt 28 having the rear end of the cable or music wire 12 connected thereto. Thence the cable 12 extends forwardly through a guide hole 29 through the center of the cross plate structure 26, and further forwardly, as indicated in FIG. 4.
The coil springs 22, as symmetrically spaced by their forward and rear connections, in effect encage or delineate a space corresponding to a fallen truncated pyramid, with a horizontal, hypothetical axis through such space comprising a co-axial extension of the normally extending cable or music wire axis. This axis is normally constrained in the horizontal by its rearward connection to eyelet of anchor bolt 28 and passage through the guide hole 29 of the connection plate 26.
The music wire or cable 12 normally extends horizontally between frames or uprights 10 and 11, and forwardly, at the backboard 30, passes through a central slot 31, with longitudinal axis in the vertical, as best shown in FIG. 5. At its forward end the music wire or cable 12 is connected to the eyelet of a forward anchor bolt 32. The rearward threaded end of the anchor bolt 32 is firmly, adjustably fixed, as by nuts, and nuts acting as lock nuts, to a cross-member or channel 33 that extends centrally across between two upright angles 34a, 34b, that form the forward, or adjustably, elevationally connectable members of the backboard assembly 35, by which it is connected by bolts to the upright of the forward frame 11. See FIG. 3. Four rearwardly, horizontally extending angles 36a, 36b, 36c, 36d with forward ends connected upwardly and downwardly, respectively, to tops and bottoms of the upright angles 34a, 34b, are indicated in FIG. 5 as having their rearward ends, not shown, rigidly, firmly and strongly connected to the forward surface (back face) of the backboard 30, thus to cantilever this member to upstand vertically. The backboard contact area is symmetrically disposed with relation to the slot 31, while a stop sleeve 37, slid over the music wire 12 and through the slot 31, has its forward end stopped at, or affixed to, the eyelet at the rear of the forward anchor bolt 32, with the rearward end of the stop sleeve 36 terminating at a predetermined convenient position a short distance rearwardly, of the backboard. Thus, as the ball is batted, the slide bushing 13 is stopped by contact with the stop sleeve 37 at the end of its forward travel, and the ball 15, tethered by the cord 14, swings against the backboard 30.
Noticeably, the batter may swing at the ball in a directed blow calculated normally to knock an infield grounder, or a high fly, or a line drive in any direction, or in directed elevation to achieve a hit to left, center or right field, and correspondingly the ball 15 tends to move at first in the exact direction imparted by the directed blow. However this direction of movement, (unless the direction of advance for the ball is straight ahead and at its normally suspended elevation) will be opposed by the relatively taut, horizontally extended music wire or cable 12, from rearward to forward anchor bolt eyelets 28, 32. The cable or music wire 12 at first tends to yield, at least in part, to the force and direction of the blow exerted on the ball, and responsive to this deflection, the axis of the spring cage 21a shifts slightly responsively. As the guide hole 29 is a bit over-sized with relation to the diameter of the cable or music wire 12, the rearward part of the cable 12 may shift correspondingly, responsive to the blow and its force and direction applied to the ball 15.
But still the ball 15 is tethered to the slide bushing 13 by the braided cord 14, and the length thereof, so the ball 15 can only straighten the cord 14 to extend substantially in direction of the blow, while after achieving this status, the ball 15 and cord 14 then tend to travel along with the sliding of the slide bushing 13 toward the forward end of the wire 12 which has responded less and less to deflection successively forwardly.
As the slide bushing 13 arrives at the end of forward travel and is brought to a stop by contact with the stop sleeve 37, the ball 15 still travels on still from result of bat impact. Now the arc of travel starts from the stopped slide bushing 13 as center, and with cord length as radius, swings the ball 15 into contact with the backboard 30, at some point of contact lower than the elevation the ball 15 first achieved when struck by the bat.
The force with which the ball 15 rebounds, (if the ball has been struck with any effective degree of force), is ample to start the slide bushing 13 rearwardly, to carry the tethered ball 15 back to batting area location.
Noticeably, as shown in FIG. 6, the ball 15 is of latex or of similar material, as of a live but wear resistant rubber. The cord 14 may be of a stout fiber, plaited to prevent unraveling, as would occur in the case of entwined strings or filaments. Its inner end is tied to, or knotted around a light, durable spool member 38, which is disposed centrally in the ball 15, the ball being molded. From the spool 38 the cord outer part is a radial line molded into the ball 15. Thence the plaited cord extends to the slide bushing exterior, also of spool shape 39, as shown in FIG. 6. The slide bushing 13 should be substantially weightless, or as light as possible, and designed to slide upon the music wire 12 with minimum friction. Thus the exterior part or spool 38 may best be of aluminum, with the bore 40 bushed at either end with light, but highly wearable bronze, or brass 41a, 41b.
The backboard 30 may be mounted at a relatively higher elevation, at a relative lower elevation, or at the elevation shown in FIG. 1, with relation to the spring cage assembly 21. In the first case the ball 15, upon rebound, would approach the batter at a slightly downward travel; in the second case the ball approach would be at a slightly upwardly travel; and in the third case the ball approach would be substantially horizontally. Also, although not shown in FIG. 2, positions of the batters plate may be imagined with forward right corner of plate slightly to the left and to the rear of the ball as shown, for right handed batters; and with forward left corner of the plate slightly to the right and to the rear of the ball as shown, for left handed batters. Obviously various plate positions and various relative backboard positions may be used in combination to simulate out of the ordinary batting conditions, as against pitchers with out of the ordinary styles of delivery.
The invention is not limited to the structural arrangements and combinations of elements shown in the drawings and described in the specification, but the broad spirit of the invention admits a wide range of structural arrangements and combinations of elements as falling within the range thereof. Also, the appended claims are by way of introduction and not by way of limitation.