US3640262A

US3640262A - Trajectory control mechanism for ball pitching machine

Info

Publication number: US3640262A
Application number: US64315A
Authority: US
Inventors: Paul Robert Hunsicker
Original assignee: Commercial Mechanisms Inc
Current assignee: Commercial Mechanisms Inc
Priority date: 1970-08-17
Filing date: 1970-08-17
Publication date: 1972-02-08
Anticipated expiration: 1989-02-08

Abstract

A ball-throwing machine having a throwing arm rigidly mounted on a rotatable shaft and a crank secured to the shaft for effecting a drive coupling provided with a force mechanism for acceleratedly driving the throwing arm through a portion of its path of travel to throw a ball. An elongated support structure is pivotally mounted with respect to the frame of the machine and supports the force mechanism for movement longitudinally of the structure. In this manner the line of force of tension spring means which comprises the mechanism is varied relative to the path of travel of the throwing arm. Thus, the point of application of the accelerative driving force, which is applied to the throwing arm as the latter reaches an overcenter position in its path of travel, is varied to alter the trajectory of a ball being thrown. A mounting component of the force mechanism has a locking element in the form of spring-biased detent means which is interengageable with a corresponding locking element in the form of a plurality of slots in the support structure. These cooperating elements are selectively interengageable to lock the spring means relative to the supporting frame of the machine. Springs bias the interengageable elements into their normal locking positions and a camming surface of the support structure is movable against the action of one of the springs to disengage the locking elements and permit swinging of the spring means longitudinally of the structure.

Description

United States Patent Hunsicker I 15] 3,640,262 [45'] Feb. 8, 1972 [54] TRAJECTORY CONTROL MECHANISM FOR BALL PITCHING MACHINE [72] Inventor: Paul Robert Hunsicker, Kansas City, Kans.

[73] Assignee: Commercial Mechanisms, Inc., Kansas City, Mo.

[22] Filed: Aug. 17, 1970 [21] Appl.No.: 64,315

52 us. c1. ..124/7, 124/36 511 Int. Cl ..F4lb3/04 [58] Field oiSearch.... ,...124/7, 36, 41, 6; 273/96 R, 273/101, 26 1) [56] References Cited UNITED STATES PATENTS 2,815,743 12/1957 Brunderman ..124/7 3,136,308 6/1964 Giovagnoli.... .....124/7 3,252,453 5/1966 Giovagno1i.... .....l24/7 3,420,218 1/1969 Rademacher.... .....124/7 Primary Examiner-Richard C. Pinkham Assistant Examiner-William R. Browne AttomeySchmidt, Johnson, Hovey,Williams Kahelin ..124/7- [57] ABSTRACT A ball-throwing machine having a throwing arm rigidly mounted on a rotatable shaft and a crank secured to the shaft for effecting a drive coupling provided with a force mechanism for acceleratedly driving the throwing arm through a portion of its path of travel to throw a ball. An elongated support structure is pivotally mounted with respect to the frame' of the machine and supports the force mechanism for movement longitudinally of the structure. In this manner the line of force of tension spring means which comprises the mechanism is varied relative to the path of travel of the throwing arm. Thus, the point of application of the accelerative driving force, which is applied to the throwing arm as the latter reaches an overcenter position in its path of travel, is varied to alter the trajectory of a ball being thrown. A mounting component of the force mechanism has a locking element in the form of spring-biased detent means which is interengageable with a corresponding locking element in the form of a plurality of slots in the support structure. These cooperating elements are selectively interengageable to lock the spring means relative to the supporting frame of the machine. Springs bias the interengageable elements into their normal locking positions and a carnming surface of the support structure is movable against the action of one of the springs to disengage the locking elements and permit swinging of the spring means longitudinally of the structure.

10 Claims, 7 Drawing Figures SHEET 1 OF 2 INVENIQR. Paul Robert Hunslcker' flTTORNEYS.

TRAJECTORY CONTROL MECHANISM FOR BALL PITCI-IING MACHINE This invention relates to ball-throwing machines and, more particularly, to novel means for varying the trajectory of a ball thrown by a machine.

A shortcoming of prior ball-throwing machines both for baseballs and tennis balls has been the absence of satisfactory mechanisms for varying the trajectory of a ball being thrown. Prior devices have utilized various types of mechanical linkages to alter the ball-trajectory but, in general, such devices have proved unreliable and difficult to manipulate. This is a particular disadvantage when a machine is used by a professional athlete since such persons normally desire to vary the ball trajectory at frequent intervals to challenge and improve their skills.

It is, therefore, an object of the present invention to provide a ball-throwing machine having force mechanism which is movable to vary the trajectory of a ball thrown in a manner which can be effected by an attendant or a player in a quick and simple movement.

Another object of the invention is a ball-throwing machine having force mechanism which utilizes an elongated support structure for mounting the spring means of the force mechanism and with the spring means being movable longitudinally of the structure to vary the line of force applied to the throwing arm and hence the trajectory of a thrown ball.

Still another object of the invention is a ball-throwing machine as set forth in the foregoing object wherein the force mechanism includes interengageable elements for locking the spring means in any one of a plurality of positions relative to the support structure.

Yet another aim of the invention is a ball-throwing machine as set forth in the foregoing object wherein the support structure comprises a crank rod which is movable against the action of a retaining spring to unlock'the interengageable elements and thereby permit movement of the spring means relative to the mounting structure.

It is also an object of the invention to provide a force mechanism for a ball-throwing machine which is movable to vary the line of application of the force and hence the trajectory of a thrown ball as set forth in the foregoing objects, and which utilizes a bellcrank to couple the spring means of the mechanism to the throwing arm so as to maximize the efficiency, durability, and effectiveness of the force mechanism.

In the drawings:

FIG. I is a side elevational view of a ball-throwing machine employing the accelerative driving force mechanism;

FIG. 2 is an enlarged elevational view of the apparatus shown in FIG. I from the opposite side of that shown in FIG. 1 and with portions being broken away;

FIG. 3 is a cross-sectional view taken along line 3-3 of FIG. 2;

FIG. 4 is a cross-sectional view taken along line 4-4 of FIG. 2;

FIG. 5 is an enlarged, cross-sectional view through the mounting component which mounts the spring means of the force mechanism and illustrating the interengageable elements on the component and the support structure in their normal locking dispositions;

FIG. 6 is a cross-sectional view similar to FIG. 5 but with the crank arm which comprises the elongated support structure being rotated 90' to unlock the interengageable elements; and

FIG. 7 is an enlarged, side elevational view of the end of the elongated support structure which is secured to the frame of the machine and illustrating the manner in which the structure is biased into a locking position.

Referring initially to FIG. 1 of the drawings, itis seen that the ball-throwing machine comprises a frame element 10 provided with a ball-throwing structure 12, and an accelerative drive force mechanism 14. The frame element 10 comprises a generally L-shaped tubular component having a horizontal arm 16 and vertical arm I8. A third arm 20 of rounded L configuration extends from one end of the arm I6 to the uppermost end of the arm 18. A tubular bar (not visible in FIG. 1) or other appropriate structure is rigid with and perpendicular to the arm 16 to provide support for a shaft 22 extending in the same direction. The shaft 22 mounts a pair of wheels, one of which is visible in FIG. I and designated by the numeral 24. A sleeve 26 at the end of the arm 16 opposite the wheel 24 receives a caster wheel assembly 28. A bracket 30 is welded or otherwise secured to the arm 16 at a point approximately midway between the ends of the latter, and the bracket extends upwardly away from the arm for purposes to be made clear hereinafter.

Referring now to the details of the throwing structure 12, a circular cup-shaped member 32 of C-shaped cross section (as best illustrated in FIG. 3) is secured to the frame element 10 by the aforementioned bracket 30 and a second bracket 34 which is rigid with and extends downwardly from the arm 20 as best illustrated in FIG. 4. A sleeve 36 extends through an appropriate size opening in the member 32 and is rigid with the latter as well as with the bracket 34. This sleeve supports a drive shaft 38 which projects outwardly on either side of the cup-shaped member 32. The drive shaft 38 supports a drive sprocket 40 which is rotatably mounted relative to the shaft and a throwing arm 42 which is rigid with the shaft. The drive sprocket 40 has a protruding pin 44 thereon which is disposed for engagement with a lug 46 carried by the arm 42. The drive mechanism for rotating the sprocket 40 and hence the arm 42 includes a conventional electric motor (not shown) having an output shaft 48 and a pulley 50 rigid with the latter. A second pulley 52 is supported for rotation upon the member 32 and is coupled with the first pulley 50 by a belt 54. A second belt 56 couples the pulley 52 with a third pulley 58 also rotatably mounted on the member 32. A drive chain 60 then couples the pulley 58 with the sprocket 40. A ball delivery mechanism 62 is mounted on the member 32 adjacent an opening 64 in the latter and supplies balls to the arm 42 in a manner to be explained more fully hereinafter.

The details of the drive force mechanism 14 are illustrated in FIGS. 3-7 which will be referred to in the following detailed description. The bracket 30 serves to mount an elongated support structure in the form of a linear crank rod 66 on the frame element 10 by means of an L-shaped support 68 which is pivotally coupled with the bracket 30 by a bolt 70. The crank rod 66 is, in turn, rotatable within the L-shaped support 68. The crank rod 66 is of generally circular cross section and, as best illustrated in FIG. 5, includes a slotted portion having a plurality of projections 72 which define a plurality of spaced slots therebetween and an arcuate surface 74 adjacent each of the slots. A torsional spring 76 at the end of the rod 66 ad jacent the support 68, biases the rod 66 into the disposition illustrated in FIG. 5 with the slot-defining projections 72 facing upwardly. One end of the rod 66 presents a handle 78 (FIG. I) for rotating the rod against the action of the spring 76.

A mounting component designated generally by the nu metal 80 in FIGS. 3 and 4 serves to mount tension spring means 82 on the crank rod 66. The mounting component 80 includes a mounting block 84, a generally horizontal support member 86, and a generally perpendicular support arm 88. The mounting block 84 has a passageway which extends from one end of the block to the other for slidably mounting the block on the rod 66. A vertical opening in the block 84 is threaded to receive a hollow bolt 90. The bolt has an opening in the bottom thereof which communicates with the longitudinally extending passageway in the block 84, and the bolt receives, within its hollow interior, a detent 92 which is biased in the direction of the passageway by a coil spring 94. A retaining screw 96 holds the detent 92 and the spring 94 within the bolt 90. A studbolt 98, which is welded or otherwise secured to the mounting block 84, forms a rigid, threaded projection on the latter. A sleeve I00 on the bolt 98 provides a pivotal mounting for the tubular support member 86 which is welded or otherwise secured to the sleeve. The support arm 88 is rigid with the member 86 and is likewise rigid with a journal sleeve 102 which pivotally mounts the arm 88 on one end of i the shaft 38. A tubular component 104 is rigid with the arm 88 and extends transversely of the latter adjacent the member 86 to provide a journal support for a shaft 106.

A bellcrank comprised of a pair of spaced plates 108 which are interconnected by a pair of

bolts

110 and 112 is rigid with the shaft 106. The member 86 is provided with a brace 114 which projects outwardly therefrom, and the latter mounts a holding plate 116 for securing one end of the spring means 82. The brace 114 is also provided with a handle 118 which projects in the opposite direction to the spring means 82. The spring means 82 is comprised of four tension springs 120, each having one end secured to the holding plate 116, and an opposite end secured to a second holding plate 122. The holding plate 122 is, in turn, secured to a connecting link comprised of a pair of spaced plates 124 by a pivotal connection 126. The plates 124 merge at one end into a journal coupling through which the bolt 112 is passed to couple the plates 124 to the plates 108. A plurality of slots along the upper surface of the plates 124 receives a pin 128 which extends transversely of the plates and is movable into different positions by a handle 130.

A crank 132 is keyed to the shaft 38 and extends radially therefrom for rotation therewith. The crank 132 is coupled with the bellcrank presented by plates 108 through a cable 134 which extends around a portion of the crank 132 and also passes around an appropriate fitting which is journaled on the bolt 110 intermediate the plates 108.

in operation, the drive means of the machine is actuated to rotate the shaft 48 and bring the pin 44 into engagement with the lug 46 to thereby rotate the arm 42 in a clockwise direction when viewing FIG. 1 through a first, arcuate, ball pickup portion of its circular path of travel about the shaft 38. Simultaneously with the rotation of the arm 42 the crank 132 is rotating through a first arcuate portion of its own circular path of travel about the shaft 38, which path is parallel with the path of the arm 42. As the crank 132 rotates in a counter clockwise direction when viewing FIG. 2, a force is exerted on the crank by the tension springs 120. This force increases in magnitude as the crank 132 rotates and reaches its maximum value as the crank passes an overcenter position, in its circular path of travel, relative to the line of force of the tension spring means 82. The arm 42 is so disposed on the shaft 38 that it passes the ball delivery mechanism 62 prior to the crank 132 reaching the aforementioned overcenter position. As the arm 42 rotates past the mechanism 62, a ball to be thrown is delivered to the arm through a conventional trip linkage. Once the crank 132 has reached its overcenter position relative to the line of force of the spring means 82, the potential energy which has been built up within the latter is released as kinetic energy acting upon the crank 132 to thereby acceleratively drive the arm 42 through a second arcuate portion of its path of travel to thereby throw the ball previously deposited in the arm. The magnitude of the accelerative driving force is variable to a certain degree by moving the pin 128 relative to the plates 124 to, in turn, vary the angle at which the pin 128 engages the plates 108 as the latter rotate on shaft 106 in response to rotation of the crank 132.

It will, of course, be appreciated that the trajectory of the ball being thrown is dependent upon the point at which the ball is released from the arm 42 in the latters circular path of travel about the shaft 38. This point is, in turn, determined by the overcenter position of the crank 132 relative to the line of force of the spring means 82 since it is at this overcenter position that the potential energy of the spring means 82 is released into kinetic energy to acceleratively drive the arm 42. The overcenter position is varied by moving the spring means 82 longitudinally of the crank rod 66. Since the

springs

76 and 94 nonnally bias the slotted portion of the rod 66 and the detent 92 into interengagement to preclude relative movement of the rod and the mounting block 84, the handle 78 is first turned to rotate the rod 66 approximately 90. This brings the arcuate surface 74 into engagement with the detent 92 and cams the latter upwardly against the action of the spring 94 as illustrated in FIG. 6. With the rod 66 maintained in this position the block 84 is movable along the length of the rod into any one of a plurality of positions. As the block 84 is moved along the length of the rod 66 the latter is pivoted upwardly because of the rigid connection formed by the support arm 88. Once the proper position of the spring means 82 along the length of the rod 66 is obtained, the latter is released to return it to its normal locking position under the action of the spring 76. This allows the detent 92 to be positioned within an appropriate slot under the action of the spring 94. The spring means 82 and its associated mounting component are illustrated in phantom in FIG. 2 as they would appear after being moved longitudinally of the crank rod 66 in the direction of the handle 78. Once the relative positioning of the rod 66 and the spring means 82 has been accomplished, the machine is again ready for operation and the trajectory of a thrown ball will be varied in accordance with the new overcenter position of the crank 132 relative to the line of force of the tension spring means 82.

From the foregoing description it will be appreciated that the ball-throwing machine of the present invention provides mechanism which is operable by an attendant or a player to vary the trajectory of a thrown ball quickly and accurately. Since the mechanism is always returned to its locking position once an adjustment has been made, there is no danger of a careless operator leaving the apparatus in an unlocked position which could result in injury to a person or damage to the machine.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

1. In a ball-throwing machine:

a frame element;

a shaft rotatably mounted on said element;

a throwing arm rigidly mounted to the shaft;

a crank rigidly secured to the shaft and extending radially therefrom, said arm and said crank being disposed for travel through parallel circular paths about the shaft;

drive means for driving said arm and said crank through a first arcuate portion of their respective paths of travel;

means for supplying a ball to said am during travel of the latter through said first portion of the circular path;

a pivoted elongated support structure mounted on said element;

a mounting component disposed on said structure and movable through an arc;

tension spring means carried by said component,

one end of said spring means being coupled to said crank for exerting a force on the latter and acceleratively drive said arm through a second arcuate portion of its respective path of travel to throw a ball after said crank reaches an overcenter position on its path of travel about the axis of the shaft said spring means being movably fixed in a plurality of radial positions about said shaft for varying the position at which the throwing arm commences accelerative movement and thus varying the point at which a ball leaves the path of travel of the throwing arm, the trajectory of a ball being thrown being varied with rotation of said spring means; and

means for locking said component in any one of a plurality of radial positions.

2. Apparatus as set forth in claim 1, including a bellcrank; means pivotally mounting said bellcrank on said component intermediate said one spring end and the first-mentioned crank, said one spring end being coupled to said bellcrank; and means for coupling said bell crank to the first-mentioned crank.

3. Apparatus as set forth in claim 1, wherein said mounting component includes an arm pivotally mounted on said shaft, said support structure being pivotally mounted on said element.

4. Apparatus as set forth in claim 3, wherein said structure is linear and said component is pivotally mounted on said structure to permit swinging thereof as necessary during movement of the component longitudinally of the structure as the latter pivots relative to said element.

5. Apparatus as set forth in claim 4, wherein said locking means includes selectively interengageable elements between said component and said structure.

6. Apparatus as set forth in claim 5, wherein said interengageable elements include a slotted portion of said structure having a plurality of projections defining spaced slots therebetween and a detent on said component disposed to be received in any one of the slots in said portion depending upon the relative location of the component with respect to the structure.

7. Apparatus as set forth in claim 5, wherein said slotted portion is normally disposed in engagement with said detent and said structure is rotatable for disengaging said detent from the slotted portion; and including first spring means biasing said structure into said normal disposition thereof, and second spring means biasing said detent into engagement with said structure.

8. Apparatus as set forth in claim 7, wherein said structure includes an arcuate surface adjacent said slotted portion, said surface acting as a cam to deflect said detent out of engagement with said slotted portion as said structure is rotated against the bias of the first spring means,

9. Apparatus as set forth in claim 8, wherein said structure comprises a crank rod presenting a handle for effecting manual rotation thereof.

10. In a ball-throwing machine provided with a frame rotatably carrying a ball-throwing arm mounted on the frame for pivoting movement about a fixed axis, structure operably associated with the arm for rotating the latter through a first, ball pickup part of its arcuate path of travel, a spring unit pivotally mounted on the frame in spaced relationship from said axis, and a crank arm assembly operably joining the spring unit to the arm for acceleratively driving the latter through another ball-throwing part of its arcuate path when the crank of said assembly moves overcenter with respect to the line of pull thereon by said spring unit, the improvement comprising:

an elongated locking member means for pivotally mounting the locking member on the frame, said frame being positioned adjacent said spring unit; and a component pivotally joined to said spring unit and said component being slidably connected to the locking member said component and said spring unit being pivoted in unison about the fixed axis, said locking member being provided with selectively operable, interengageable locking mechanism permitting shifting of the component and thereby pivoting of the spring unit and component to vary the overcenter position of the crank arm when the locking member is in a selected position on said locking member and thereby fixedly securing the component and the spring unit in a selected pivoted location relative to the fixed axis.

Claims

1. In a ball-throwing machine: a frame element; a shaft rotatably mounted on said element; a throwing arm rigidly mounted to the shaft; a crank rigidly secured to the shaft and extending radially therefrom, said arm and said crank being disposed for travel through parallel circular paths about the shaft; drive means for driving said arm and said crank through a first arcuate portion of their respective paths of travel; means for supplying a ball to said arm during travel of the latter through said first portion of the circular path; a pivoted elongated support structure mounted on said element; a mounting component disposed on said structure and movable through an arc; tension spring means carried by said component, one end of said spring means being coupled to said crank for exerting a force on the latter and acceleratively drive said arm through a second arcuate portion of its respective path of travel to throw a ball after said crank reaches an overcenter position on its path of travel about the axis of the shaft said spring means being movably fixed in a plurality of radial positions about said shaft for varying the position at which the throwing arm commences accelerative movement and thus varying the point at which a ball leaves the path of travel of the throwing arm, the trajectory of a ball being thrown being varied with rotation of said spring means; and means for locking said component in any one of a plurality of radial positions.

8. Apparatus as set forth in claim 7, wherein said structure includes an arcuate surface adjacent said slotted portion, said surface acting as a cam to deflect said detent out of engagement with said slotted portion as said structure is rotated against the bias of the fIrst spring means.

10. In a ball-throwing machine provided with a frame rotatably carrying a ball-throwing arm mounted on the frame for pivoting movement about a fixed axis, structure operably associated with the arm for rotating the latter through a first, ball pickup part of its arcuate path of travel, a spring unit pivotally mounted on the frame in spaced relationship from said axis, and a crank arm assembly operably joining the spring unit to the arm for acceleratively driving the latter through another ball-throwing part of its arcuate path when the crank of said assembly moves overcenter with respect to the line of pull thereon by said spring unit, the improvement comprising: an elongated locking member means for pivotally mounting the locking member on the frame, said frame being positioned adjacent said spring unit; and a component pivotally joined to said spring unit and said component being slidably connected to the locking member said component and said spring unit being pivoted in unison about the fixed axis, said locking member being provided with selectively operable, interengageable locking mechanism permitting shifting of the component and thereby pivoting of the spring unit and component to vary the overcenter position of the crank arm when the locking member is in a selected position on said locking member and thereby fixedly securing the component and the spring unit in a selected pivoted location relative to the fixed axis.