Automatic hoist system for backstop assembly

July 1, 1969 j. n. miller etal 3,452,984

AUTOMATIC HOIST SYSTEM FOR BACKSTOP ASSEMBLY

Filed June 20, 1966 Sheet ¹ of 2

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F I G. 2 .

INVENTORS

JOSEPH N. MILLER ARTHUR G. HARBAUGH

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ATTORNEYS

July .1, 1969 j. n. miller etal 3,452,984

AUTOMATIC HOIST SYSTEM FOR BACKSTOP ASSEMBLY

Filed June 20, 1966 Sheet 2 of 2

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INVENTORS

JOSEPH N. MILLER

ARTHUR G.HARBAUGH

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3,452,984

Patented July 1, 1969

United States Patent Office

3,452,984 AUTOMATIC HOIST SYSTEM FOR BACKSTOP ASSEMBLY

Joseph N. Miller, Overland, and Arthur G. Harbaugh, St. Louis, Mo., assignors to Jackes-Evans Manufactur- 5 ing Company, St. Louis, Mo., a corporation of Missouri

Filed June 20,1966, Ser. No. 558,817

Int. Cl. A63b 71/04; B66f 11/00

U.S. Cl. 273—1.5 7 Claims

ABSTRACT OF THE DISCLOSURE

A hoisting arrangement for a folding backstop assembly of the forward-swing type where the hoisting cable is located over the field of play. A retracting means is 15 operatively connected to a position control switch and maintains the hoisting winch energized to provide slack in the cable after the backstop is fully down and simultaneously pulls the cable upwardly out of the area of play so as to not interfere with the trajectory of the 20 basketball. A novel circuit including a position control switch for the raised position is also shown.

This invention relates to automatic hoist systems for 25 backstop assemblies of folding types..

A power operated winch for retractable backstops has heretofore required the operator to be in sight of the backstop for regulating the raising and lowering operation to prevent overrunning the winch. The problem in 30 raising a backstop is stopping the power winch at the proper time to prevent stressing the backstop supports or stretching the hoisting cable. Conversely, in lowering the backstop the problem is to properly time the power winch so that the backstop is fully down and to avoid 35 excessive unwinding of the hoist reel. Furthermore, when control devices are employed they do not accurately take into account the cable stretch so that improper lowering of the backstop often results, and raising the backstop with the use of timing devices often results in incom- ⁴⁰plete retraction.

It is therefor an important object of this invention to overcome the problems heretofore encountered with power retracted backstops by a simple yet unique backstop hoist control system that automatically accounts 45 for cable stretch and accurately positions the backstop.

_ It is also an important object of this invention to provide ,an automatic hoist system for backstops that may be located remotely from the backstop and does not require the visual attention heretofore demanded. 50

A further object of this invention is to provide means directly responsive to the movement of the foldable backstop for controlling the power winch in both the retraction and lowering phases of movement.

Yet another object of this invention is to provide 56 an automatic hoist system for foldable backstops that will prevent excessive winding and unwinding of the power winch to protect the operating components of the system and yet assure proper raising and lowering operation. 60

Still other objects and advantages of the present invention will be set forth in connection with the parts, components and elements of a presently preferred folding backstop system to be hereinafter described with reference to the accompanying drawings, wherein: 65

FIG. 1 is a perspective view of a folding backstop having the automatic hoisting means and controls therefor which will exemplify the principles of the invention, the backstop being seen when lowered into playing position; 70

FIG. 2 is a side view of the backstop when folded, certain components being omitted for the sake of clarity;

FIG. 3 is an enlarged fragmentary sectional view taken at line 3—3 in FIG. 1 of the backstop lowering control means;

FIG. 4 is a greatly enlarged sectional view of the control switch for the lowering control means of FIG. 3;

FIG. 5 is a fragmentary perspective view of the raising control means incorporated in the view of FIG. 1; and

FIG. 6 is a wiring diagram of the control system.

The drawings forming a part of this specification ilustrate a backstop of forward folding character which will serve to disclose the principles of the invention. It is within the preview of the invention to apply the automatic hoist system to other types of foldable backstops.

In FIG. 1 the backstop assembly 9 includes a backboard 10 to support the usual goal and net 11 in normal playing position. The backboard is rigidly connected by brackets 12 to a pair of parallel tubular drop members 13 which are held in spaced relation by upper and lower spacer members 14. The members 13 are hingedly fastened to a horizontal tubular member 15 by means of hinge clamps 16 secured on members 15 and hinge ends 17 secured to the upper ends of the drop members 13.

The backboard 10 is braced in its down or playing position by brace members 18 that are crossbraced by member 19. The upper ends of the brace members 18 have hinge ends 20 connected to hinge clamps 21 similar to the connections for members 13 and 15. The lower ends of the brace members 18 are provided with slide fittings including a hinge end element 22 connected to slide sleeves 23 having adjustment elements 24 that cooperate with the brackets 25 of vertical guide rods 26. The upper ends of the guide rods 26 are provided with brackets 25, and both upper and lower brackets 25 (FIG. 2) are attached by clamps 27 to the members 13 supporting the backboard 10.

It is seen in FIGS. 1 and 2 that the braces 18 are hingedly connected to a horizontal tubular member 28, in a manner similar to the members 13. The two tubular members 15 and 28 are rigidly connected by suitable fittings 29 to a pair of overhead structural members 30 which may be a part of a building structure, or may be specially provided to support the backstop structure as shown in FIG. 1. In FIG. 2 the folded position of the assembly illustrates the character of movement of the slide sleeves 23 on guide rods 26, and especially the movement of drop members 13 relative to the horizontal member 15.

The means for automatically raising and lowering the backstop, while generally located in FIG. 1, is shown best in FIGS. 3, 4 and 5, and in the wiring diagram of FIG. 6. In FIGS. 1, 3 and 4 the horizontal member 15 supports a clamp 32 for mounting a normally closed limit switch 33 by means of a 'bracket 34. The switch button 35 is engaged by an actuator element 36 mounted in a bearing sleeve 37 on the bracket. The element is provided with a stop sleeve 38 of suitable length to limit the compression of the spring 39 by the adjusting nuts 40 which collapse the spring 39 when the actuator element is displaced by a pull chain 41 connected at the loop 42. The direction of pull of the chain 41 can be adjusted by rotating the clamp 32 on member 15.

The chain 41 extends from its connection at loop 42 to a pulley 43 connected to the adjacent drop member 13 by a clamp 44 where there is provided means to connect one end of a slack take-up spring member 45.

The take-up spring member 45 has its opposite end connected to a pulley 47 through which is reeved the hoist cable 48. One end of the cable 48 is connected to an anchor eye 49 fixed to the spacer member 14 adjacent the backboard 10. The other end of cable 48 is reeved

3,452, through pulley 50 attached to overhead spacer 51 for the members 30 and through side pulley 52 before being connected to the drum or reel (not shown) of a.power winch 53. The winding reel is enclosed in casing 54 which supports a gear drive unit 55 having its pulley 56 driven by belt 57 from motor 58. A reversing switch 59 is connected by conduit 60 to the motor 58 so that the cable can be wound up to hoist the backstop assembly 9 or can be unwound to lower it. The switch 33 controls the lowering of the backstop assembly as will be ex- ιθ plained presently. It is to be understood that the rm “cable” shall include any flexible hoisting means such as a rope, a chain, solid or stranded wire rope, or the like.

In FIG. 5 there is shown a switch 61 mounted by clamp 62 on the support member 15 adjacent one of the 75 drop members 13 which is hinged at 16-17 to member 15. The switch 61 has its button 63 located to be actuated by means 64 adjustably mounted on bracket 65 carried by member 13. The switch 61 is normally closed when the backstop is lowered, but opens the circuit when, on hoist- 20 ing the backstop assembly 9, the actuator means 64 hits button 63 and opens switch 61. Th switch 61, as well as actuator 64, may be positionally adjusted by the clamp means employed.

Referring now to FIG. 6, the circuit layout includes 25 a source of electrical current EC having one lead 66 connected to the motor 58 and another lead 67 connected to the center tap of the reversing switch 59. From reversing switch 59, one lead 68 connects to the limit switch 33 and from there a lead 69 connects to motor 58. An- 30 other lead 70 connects to the limit switch 61, and from there lead 71 connects to motor 58.

With the present apparatus properly adjusted and installed, and the assembly 9 in lowered playing position, the switch 33 will be held open by actuator 36 and switch 35 61 will be normally closed as actuator 64 is separated therefrom. The reversing control switch 59 may now be turned to the “up” position in which leads 67 and 70 will be connected to complete a circuit to winch motor 58. The action of cable 48 going taut to pick up the 40 weight of the foldable assembly will stretch out spring means 45 and eventually pull chain 41 against spring 39 so that switch 33 can reset itself to normally closed condition. Spring 45 and chain 41 have a length which is sufficient to compress spring 39. Fine adjustments for 45 actuator 36 is made at nut 40 so that the eye 42 is just clear of the sleeve 37 with the switch open. The motor 58 will continue to reel up cable 48 until the actuator 64 strikes button 63 to open switch 61 at the elevation desired for the backstop assembly. The cable 48 remains taut at 50 this time so that the spring 39 is compressed to allow switch 33 to stay in its normally closed position. Thus, when the control switch 59 is subsequently turned to its backstop “down” position, leads 67 and 68 will be in circuit with lead 69, motor 58 and lead 66 to operate motor 55 58 in a reverse direction for unreeling the cable 48.

The lowering action of the winch 53 keeps cable 48 taut until the backstop is in fully down position with its stops 24 at the bottom of slide rods 26. The winch continues to unwind the cable 48 to allow spring means 45 60 to retract or pull the cable 48 up and away from the backboard where it will not interfer with a basketball aimed at the goal 11. The take-up spring 45 at this time will contract until its reduced tension is overpowered by the compressed spring 39, and when this occurs the spring 65 39 can displace the actuator to open the switch 33. This switch opening action will stop motor 58, but not before the cable 48 has been unreeled enough to allow the retracting spring 45 to pull it up and out of the way of the area above and in front of the backboard. 70

It is believed fully clear that the assembly permits automatic retracting of the hoist cable to a position above the face of the backboard when the backstop is in its lowered position before the switch 33 automatically breaks the electrical circuit to the winch motor 58. This 75

984 breaking of the electrical circuit permits having the winch motor control switch 33 in the “on” position longer than the time required just to lower the backstop, but not long enough to completely unwind the cable on the winch past the “unwound” condition where it would start to rewind in the opposite direction. In the raised position and during the lowering operation, the backstop hoist cable is taut from the weight of the backstop which pulls the retractor cable pulley forward. This pull transfers through the retractor cable and exerts tension on the extension spring which in turn pulls the switch actuator bolt 36 down, releasing the switch to the normally “closed” position, closing the circuit for lowering the backstop. The spring 39 on the actuator bolt 36 provides pressure to actuate switch 33 when tension is off of the retract spring 45. Additional pressure adjustment is made by means of the spring adjustment nuts 40, if adjustment is required, to overcome the weight of the retraction spring and cable assembly. Use of the “up” and the “down” limit switches 33 and 61 provides automatic control of raising and lowering the backstop assembly 9 without the operator of the control switch 59 being in sight of the backstop.

The foregoing description relates to a preferred embodiment of this invention, but all modifications that fall within the scope of the appended claims are to be included wherever possible.