CA2109908A1 - Bungee jumping and catapulting apparatus - Google Patents
Bungee jumping and catapulting apparatusInfo
- Publication number
- CA2109908A1 CA2109908A1 CA002109908A CA2109908A CA2109908A1 CA 2109908 A1 CA2109908 A1 CA 2109908A1 CA 002109908 A CA002109908 A CA 002109908A CA 2109908 A CA2109908 A CA 2109908A CA 2109908 A1 CA2109908 A1 CA 2109908A1
- Authority
- CA
- Canada
- Prior art keywords
- ladder
- cable
- bungee cord
- jumping
- user
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 230000009191 jumping Effects 0.000 title claims abstract description 74
- 239000003381 stabilizer Substances 0.000 claims description 6
- 230000009194 climbing Effects 0.000 claims description 5
- 230000000717 retained effect Effects 0.000 claims description 3
- 238000004904 shortening Methods 0.000 claims description 3
- 230000000712 assembly Effects 0.000 claims description 2
- 238000000429 assembly Methods 0.000 claims description 2
- 230000000903 blocking effect Effects 0.000 abstract 1
- 210000002414 leg Anatomy 0.000 description 5
- 230000010355 oscillation Effects 0.000 description 5
- 239000002184 metal Substances 0.000 description 3
- 230000008602 contraction Effects 0.000 description 2
- 239000012530 fluid Substances 0.000 description 2
- 210000002445 nipple Anatomy 0.000 description 2
- 230000000087 stabilizing effect Effects 0.000 description 2
- 230000009182 swimming Effects 0.000 description 2
- 241001503987 Clematis vitalba Species 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000006378 damage Effects 0.000 description 1
- 230000000994 depressogenic effect Effects 0.000 description 1
- 239000002984 plastic foam Substances 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 210000000689 upper leg Anatomy 0.000 description 1
Classifications
-
- E—FIXED CONSTRUCTIONS
- E06—DOORS, WINDOWS, SHUTTERS, OR ROLLER BLINDS IN GENERAL; LADDERS
- E06C—LADDERS
- E06C5/00—Ladders characterised by being mounted on undercarriages or vehicles Securing ladders on vehicles
- E06C5/02—Ladders characterised by being mounted on undercarriages or vehicles Securing ladders on vehicles with rigid longitudinal members
- E06C5/04—Ladders characterised by being mounted on undercarriages or vehicles Securing ladders on vehicles with rigid longitudinal members capable of being elevated or extended ; Fastening means during transport, e.g. mechanical, hydraulic
-
- A—HUMAN NECESSITIES
- A63—SPORTS; GAMES; AMUSEMENTS
- A63B—APPARATUS FOR PHYSICAL TRAINING, GYMNASTICS, SWIMMING, CLIMBING, OR FENCING; BALL GAMES; TRAINING EQUIPMENT
- A63B5/00—Apparatus for jumping
-
- A—HUMAN NECESSITIES
- A63—SPORTS; GAMES; AMUSEMENTS
- A63B—APPARATUS FOR PHYSICAL TRAINING, GYMNASTICS, SWIMMING, CLIMBING, OR FENCING; BALL GAMES; TRAINING EQUIPMENT
- A63B5/00—Apparatus for jumping
- A63B5/08—Spring-boards
- A63B2005/085—Spring-boards for launching, e.g. catapulting
-
- A—HUMAN NECESSITIES
- A63—SPORTS; GAMES; AMUSEMENTS
- A63B—APPARATUS FOR PHYSICAL TRAINING, GYMNASTICS, SWIMMING, CLIMBING, OR FENCING; BALL GAMES; TRAINING EQUIPMENT
- A63B5/00—Apparatus for jumping
- A63B5/16—Training devices for jumping; Devices for balloon-jumping; Jumping aids
- A63B2005/163—Free-fall jumping on elastic cords, e.g. Bungee jumping
Abstract
A ladder can be raised to a steep inclined position and a user can jump off a jumping platform carried by the top end of the ladder; the user is connected to a bungee cord which is attached to a non-elastic cable trained on a pulley disposed above the jumping platform and connected to a system to pay-out and retrieve the cable and operated by a double-acting hydraulic cylinder which can positively block the top end of the bungee cord at any desired level. Blocking is also automatically effected whenever the hydraulic pressure falls below a predetermined minimum. A catapulting arrangement is also provided to hurl the user up in the air. The cable pay-out and retrieving system serves to stretch the bungee cord to catapult and to lower the jumper to the surface upon completion of the jump or catapult. The ladder is made of modular sections which can be folded into a transport mode.
The ladder and accessories are mounted on a roadable wheeled platform for transport to and erection in different sites.
The ladder and accessories are mounted on a roadable wheeled platform for transport to and erection in different sites.
Description
2lns~0~
FIELD OF THE INVENTION
The present invention relates to an apparatus for oscillating users in a generally vertical plane by means of an elastic cord or bungee cord.
BACKGROUND OF THE INVENTION
Bungee jumping is a sport which has developed in the last decade. The user jumps off a high-level jumping platform being attached to an elastic cable or bungee cord. After his vertical oscillations have subsided, the jumper is lowered to the ground by means of a non-elastic cable attached to the bungee cord and to a winch or the like which serves to pay-out and retrieve the non-elastic cable and the bungee cord. It has been found that known bungee jumping systems lack in safety features with the result that jumpers have accidents.
Known jumping systems are also static structures being intended to be erected and permanently used on one site with the result that after a few seasons, the clientele of jumpers becomes depleted.
OBJEcTs OF THE INVENTION
The general object of the present invention is to provide a bungee jumping system which has a number of safety features to considerably reduce the occurrence of accidents to the jumpers and attending personnel.
Another object of the present invention is to provide a system of the character described which is quickly erected and dismantled and is easily transported from one site to another.
Another object of the invention is to provide a system of the character described further including a ladder provided with two jumping platforms at two different levels to accommodate jumpers of different degrees of bravery, and which ~ 2109908 can be used at the same time to increase the jumping capacity of the system.
Another object of the invention is to provide a bungee jumping system which can also be used for catapulting a user from ground level up in the air.
SUMMARY OF THE INVENTION
The apparatus of the invention serves to oscillate users in a generally vertical plane and comprises an elongated base structure, a ladder made of several ladder sections, releasable securing means to secure said ladder sections in alignment, pivotal means connecting the lower end of the ladder to the base for raising and lowering movement of the ladder in a vertical plane, power means carried by the base structure to raise the ladder to a steeply inclined operative position, a jumping platform secured to the topmost section of the ladder and protruding at an angle thereto and horizontally disposed when the ladder is in operative position, a bungee cord, means to attach one end of the bungee cord to a user, a pulley carried by the top of the ladder above the jumping platform, a non-elastic cable trained on the pulley and attached to the other end of the bungee cord and power operated means to pay-out and retrieve the non-elastic cable between a retracted position adjacent said pulley in which a user attached to said one end of said bungee cord is suspended above ground even when said bungee cord is fully stretched, and an extended position in which said one end of said bungee cord is closer to the ground and allows the attached user to land.
Preferably, the several ladder sections are serially hinged to each other for pivotal movement between an accordeon-like folded position and an unfolded aligned position, the assembly of the sections when unfolded having an ~- 2109908 overall length several times that of the elongated base structure and the assembly of the folded sections having a length generally the same as that of said elongated base structure, which is preferably a wheeled roadable base structure to be towed by a road tractor. The power operated means to pay-out and retrieve the non-elastic cable preferably consists of a double-acting hydraulic ram having a fixed end and a movable end, a fixed assembly of return pulleys at said fixed end of said hydraulic ram, a movable assembly of return lo pulleys carried by the movable end of said hydraulic ram, the non-elastic cable being trained several turns around the return pulleys and fixed at one end adjacent the fixed assembly of pulleys. Shortening and lengthening of the hydraulic ram causing pay-out and retrieving of the non-elastic cable to an amount which is a multiple of the stroke of the hydraulic ram whereby the latter can be installed on the base structure. A flow control valve automatically blocks the hydraulic ram against extension or contraction movement should the oil pressure inadvertently fall below a predetermined level.
The user, while climbing the ladder is always attached to a safety cable running along the ladder by means of a safety slider which allows ladder climbing but prevents falling movement.
Preferably the bungee cord is suspended from a pair of non-elastic cables, each of sufficient force to retain the jumper should the other cable break.
Preferably the jumping platform has safety gates arranged to delimit a jumping area accessible to one jumper at a time, one of the gates closing a ~umping orifice made in the guard rail surrounding the jumping platform, therebeing provided a spring supported pad which is linked to the gates ~4 2109908 so as to unlock one gate while locking the other and which is responsive to the presence of the user on the pad so that the jumping orifice gate is unlocked only when the jumper is standing on the pad ready to jump.
The user wears a harness to which the free end of the bungee cord is removably attached. Preferably the apparatus also includes means to serve to catapult a user from ground level up in the air and to land the user. This catapulting system includes retaining means to temporarily retain the other end of the bungee cord at ground level while the non-elastic cable means is in retracted position with the bungee cord in stretched condition and further including releasing means to release said retaining means to cause the bungee cord to pull the attached user upwardly. Preferably the retaining means includes a weighted block adapted to rest on the ground and link means linking the block to the harness, the releasing means serially connecting the link means to the harness, the block being of a weight sufficient to resist the pull of the stretched bungee cord. Preferably, a scale with a read-out is serially interposed in the link means to indicate the pull exerted by the stretched bungee cord.
BRIEF DESCRIPTION OF THE DRAWINGS
In the annexed drawings, Figure 1 is a side elevation of the bungee jumping system in transport mode;
Figure 2 is a rear end elevation of the same taken along line 2 of Figure 1;
Figure 3 is a partial elevation showing the hinge between two ladder sections and taken along line 3-3 of Figure 2;
Figure 4 is a top plan view of the trailer shown in Figure 1 and showing how the ladder sections are unfolded;
~ 21099~8 Figure 5 is a side elevation of the extended outrigger arm, this view taken along line 5 of Figure 4;
Figure 6 is a cross-section taken along line 6-6 of Figure 2 and showing the ladder raising telescopic hydraulic cylinder in retracted position;
Figure 7 is a side elevation of the ladder assembly in half-raised position on the trailer;
Figure 8 is a partial side elevation on an enlarged scale of one of the two pivotal connections of the ladder to the trailer and taken in area 8 of Figure 7;
Figure 9 is a cross-section taken along line 9-9 of Figure 8;
Figure 10 is a side elevation of the ladder and trailer with the ladder in a fully raised, operative position lS and properly stabilized by guy wires and braces ready to be used;
Figure 11 is an end elevation of the assembly of Figure 10;
Figure 12, seen on the seventh (7th) sheet of drawings, is a cutaway top plan view of the cable pay-out and retrieval system and taken in an area delimited by line 12 in Figure 4;
Figure 13 is a longitudinal section taken along line 13-13 of Figure 12;
Figure 14 is a cross-section taken along line 14-14 of Figure 12;
Figure 15, seen on the sixth (6th) sheet of drawings, shows the connection of a brace to the lower-level jumping platform and taken in area 15 of Figure 11;
Figure 16 is a partial side elevation taken in area 16 of Figure 11 and showing the pivotal connection of the lower end of a ladder brace to the platform;
~ 2109908 Figure 17 is a cross-section taken along line 17-17 of Figure 16;
Figure 18 is a partial elevation on an enlarged scale taken in area 18 of Figure 11 and showing how the top end of the ladder brace is connected to the ladder;
Figure 19, seen on the eighth (8th) sheet of drawings, is a plan section taken along line 19-19 of Figure 11 and showing the high level jumping platform;
Figure 20 is a partial vertical section taken along line 20-20 of Figure 19;
Figure 21 is a vertical cross-section taken along line 21-21 of Figure 19;
Figure 22 is a partial elevation taken along line 22 of Figure 19;
Figure 23 is a plan section taken along line 23-23 of Figure 11 and showing the low level jumping platform;
Figure 24 is a side elevation of the low-level jumping platform;
Figure 25, seen on the ninth (9th) sheet of drawings, is a partial elevation of the ladder and a front end elevation of the low-level jumping platform, and taken along line 25 of Figure 24;
Figure 26 is a partial vertical section taken in area 26 of Figure 22;
Figure 27 is a schematic plan section taken along line 27-27 of Figure 26;
Figure 28 is a partial elevation taken in area 28 of Figure 25;
Figure 29 is a schematic plan view of the system shown in Figure 28;
Figures 30 and 31 are a partial side elevation and a front elevation respectively showing the top end of the ~ 2109~08 ladder, the double pulley, and the attachment of the bungee cord to the pay-out cables, these Figures being taken in area 30 of Figure 7;
Figures 32 and 32A show the jumper harness in side elevation and back elevation and attached to the lower end of the bungee cord;
Figure 33 shows the jumper harness in front elevation while the jumper is oscillating;
Figure 34 is a partial elevation taken in area 34 of Figure 32 and showing the attachment of the lower end of the bungee cord to the harness;
Figure 35 is a partial elevation of the safety cable and safety slider; and Figure 36 is partial elevation of the catapulting system and showing the user about to be catapulted.
In the annexed drawings, like reference characters indicate like elements throughout.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The bungee jumping system comprises a ladder 2 pivoted at its lower end by hinges 4 to a base structure, namely a base platform 6 which forms the top of an elongated roadable trailer 8 mounted on tandem wheels 9 and which is hinged at its front end by a conventional fifth wheel to a driving tractor 10.
Ladder 2, which may have a length of 100 feet, is composed of a trestle-work 12 supporting a series of steps 14 (see ~igure 20) and the climber is protected by longitudinally extending guide rails 16. A low-level jumping platform 18 and a high-level jumping platform 20 are secured to the trestle-work 12 of the ladder. Ladder 2 is made of three ladder sections of substantially equal length namely, a lower section 22, an intermediate section 24 and a top section 26. As shown -~- 210990~
in Figure 4, the three ladder sections are serially hinged to each other by hinges 28 and 30 having their hinge axes normal to the hinge axis of hinge 4 and disposed on opposite sides of ladder section 24. Thus the ladder sections 22, 24 and 26 can be folded and unfolded in accordeon-like manner and in a horizontal plane, laterally of the platform 6 when the sections 22, 24 and 26 are in a horizontal position.
Obviously it is the bottom section 22 which is hinged to platfQrm 6 by the two laterally spaced hinges 4, one of which is shown in Figure 9. Hinges 4 are disposed in the front portion of platform 6. The three modular sections 22, 24 and 26 can thus take a folded position in which the three sections are disposed side by side longitudinally of the platform 6 within the lateral confines of the platform 6.
The ladder sections 22, 24 and 26, once unfolded and positioned in mutual alignment, are locked in this aligned position by bolts and nuts (not shown), the bolts inserted into holes 32 made in the ends of the trestle-work 12 of the respective ladder sections (see Figure 2). The arrangement is such that, in the transport mode, the ladder sections 22, 24 and 26 rest horizontally on the platform 6 of the trailer 8 being shorter than the latter.
A power operated means is provided to raise and lower the ladder 2 between a horizontal position and an operative position in which the ladder is steeply inclined as shown in Figure 10. These means consist of a single-acting, telescopic hydraulic cylinder 34, hinged intermediate the end of its bottom section at 36 below the platform 6 about a horizontal transverse axis. Cylinder 34 extends through an opening 38 made in platform 6 and its top end is pivoted at 40 to the upper end of the bottom ladder section 22.
Stabilizer means are provided to stabilize the ladder in its operative position. The stabilizer means (see Figures 10 and 11) includes concrete blocks 42 which serve as counterweights disposed on the front end of the platform 6, guy wires 44 and 46 which are attached to the top ladder section 26 and to the front end and at the rear end respectively of the platform 6. The stabilizer means further includes laterally extending outrigger arms 48 which laterally extend from the opposite ends of the rear end of platform 6, more specifically as shown in Figures 1, 4 and 5. Each outrigger arm 48 is made of telescopic arm sections 50 which, when in telescoped condition, are stored within a transverse retainer tube 52 fixed to the structure of the trailer 8 underneath the rear end of platform 6 such that the entire outrigger arm 48 is stored within the lateral confines of the trailer. The two outrigger arms 48 are offset with respect to the longitudinal axis of the trailer 8 so that the retainer tubes 52 are disposed side by side behind the tandem wheels 9 of the trailer 8. When extended, the telescopic arms sections 50 are locked in position by pins 54. The outermost arm section 50 carries a ground engaging, vertically adjustable leg 56, each outrigger arm 48 is reinforced against upward movement by a brace 58 and an intermediate vertical strut 60.
Both the brace 58 and strut 60 are connected to the arm sections 50 and to the trailer structure by removable pins so that they can be dismantled and stored longitudinally under the trailer platform 6 within the trailer structure.
The back guy wires 46 are preferably directly attached to the top end of the assembly of the ground engaging leg 56 and also, if found necessary, to a concrete block 62 disposed adjacent leg 56. In practice blocks 62 have been found to be unnecessary.
The stabilizing means further include (see Figures 10 and 11) a pair of rigid braces 64 each secured to the top of bottom ladder section 22 by a connection 66 ~see Figure 18) and attached at their lower end to the platform 6 by a pivotal connection 68 tsee Figure 16). The two braces 64 are downwardly diverging. Obviously, during use, the platform 6 is further stabilized by the conventional jacks 70 normally associated with a trailer and used when the driving tractor 10 is disconnected therefrom.
Figure 10 also shows a stairway 72 to allow users to step up to the platform 6 from ground level. Stairway 72 is a unit which can be disconnected form the platform 6 and stored on the latter for transport of the whole assembly.
Referring to Figures 7, 10, 11, 20 and 21, there is provided a high-level jumping platform 74 which protrudes from the underside of the ladder 2 at an obtuse angle relative to the same such that when the ladder is erected in operative position as shown in Figure 10, it will be horizontal. The jumping platform 74 is an assembly which is removably connected to the top ladder section 26 such that this section can rest flat on the trailer platform 6 when the ladder is in folded transport mode.
The steps 14 together with the guard rails 16 terminate at the platform 74 and the ladder is also provided with a guard rail 76 which has an exit opening 78 formed at the end of the cross-leg 80 of the platform 74 which is L-shaped when shown in plan section (see Figure 19).
A slidable safety gate 82 normally closes the exit opening 78; a second safety gate 84 is disposed at the entrance of the jumping platform at the end of the ladder steps 14.
A pad 86 (see Figures 19, 21, 22, 26 and 27, is horizontally positioned on the platform 74 just inside the exit opening 78. Pad 86 is guided for up and down movement between an upper and a lower position and spring pressed to an upper limit position by a pin and sleeve and coil spring assemblies 88 as shown in Figure 26. When the jumper stands on pad 86, the latter is depressed to its lowermost position and actuates a mechanism which unlocks the exit safety gate 82, SQ that the latter may be opened by an operator standing beside the jumper, and simultaneously locks the entrance safety gate 84 so as to prevent access of the next jumper to the jumping platform while the first jumper is preparing to jump. This locking and unlocking mechanism includes a rod 90 secured to the underside of pad 86 and engageable with a lever 92 which is pivoted intermediate its ends at 94 about a horizontal axis. Rod 90, upon depression of pad 86, causes lever 92 to pivot counterclockwise (see Figure 26) from its full line position to its dotted line position.
Exit safety gate 82 (see Figure 22 and 26) includes a U-shaped tube 96 slidable in sleeves 98 horizontally disposed one below the other and fixed to the guard rail 76.
Similarly, the entrance safety gate 84 includes a U-shaped tube 100 slidable in sleeves 102 which are horizontally disposed and are secured to the guard rail 74 and laterally outwardly protrudes from the same. The lower one of each sleeve 98 and 102 is provided with a nipple 104 secured to and downwardly protruding therefrom. In this nipple is mounted a locking pin 106 which is spring pressed by spring 108 into a position entering sleeve 102 and also a hole 110 made in the tube 100 when said tube is in closed position. This locking arrangement is the same for both safety gates 82 and 84.
-Each locking pin 106 is connected to a pulling rope namely a pulling rope 112 for the U-shaped tube 96 and 114 for U-shaped tube 100. The two pulling ropes are trained on pulleys 116 and are attached to opposite ends of the lever 92.
The spring 108 of the locking pin 106 which is associated with the exit gate 82 is stronger than the spring of the other gate whereby lever 92 is pulled in to the normal position shown in full line in Figure 26 wherein the exit gate 82 is locked when the same is closed and the entrance gate 84 is unlocked.
When the jumper stands on the pad 86, the exit gate becomes unlocked while the entrance gate, when in closed position, is automatically locked.
The ladder 2 is also preferably provided with a low-level jumping platform 120 as shown in Figures 7, 10, 11 and 25. This platform 120 is fixed to the top of the bottom ladder section 22 and laterally extends therefrom. It is in horizontal position when the ladder is in fully erected position as shown in Figure 10. Jumping platform 120 is releasably fixed to an angular framework 122 so that it may be removed such that the ladder in transport mode will not exceed the sides of the trailer 8. AS shown in Figures 10 and 11, the jumping platform 120 is stabilized by a pair of braces 124 which are pivotally connected to the platform 120 and to the trailer platform 6 by connector pins 126 such as shown in Figure 15. Jumping platform 120 has a guard rail 128 on both its longitudinal sides and it has an exit gate 130 (see Figures 24 and 25) and also an entrance gate 131 behind gate 130. The jumping platform 120 has also a pad 86A with a gate locking and unlocking mechanism similar to that just described in connection with the high-level jumping station and which is schematically illustrated in Figures 28 and 29, the only difference between the above described locking mechanism lies in the fact that the lever 92A has a different shape than that of lever 92 while the ropes 116A and 118A are attached to the same end of the lever 92A instead of two opposites ends thereof. Also, the positioning of the pulleys is different.
Here again, supposing the exit gate 130 is closed and locked, the same will become unlocked upon a jumper stepping on pad 86A. Simultaneously the entrance gate 131 will become locked supposing that it is in closed position.
The safety gates are shown as horizontally displaceable so that an operator must manually move the same from closed to opened position and vice versa. However it is possible to incline the sleeves 98 and 102 so that the gates will automatically take a normally closed position.
An important safety feature is the provision of safety cables which runs the whole length of the ladder 2 and along the jumping platforms 74 and 120. A ladder safety cable 132 (see Figures 20 and 25) runs along practically the whole length of the ladder 2 alongside one guard rail 16 being attached at its ends 134 and to the top of guardrail 16 and also below the low-level jumping platform (not shown).
Similarly, the high-level jumping platform is provided with a horizontal cable 138 (see Figures 20 and 22) which is attached at both ends at 140 and at 142 to that one of the guard rails 76 which is closer to cable 132. The low-level jumping platform 120 is provided with a similar cable 138A attached to guard rail 128 at 140A and 142A.
The jumper A (see Figures 32 to 35) wears a jumping harness 144 comprising a torso strap assembly 146, a waist belt 148 and thigh belts 150, connected together by strapping 152 and by front and back metal ring 154 and 156. To the waist belt 148 is attached by means of a strap 157 and of a karabiner 158 a safety slider 160 which consists of a U-shaped 210ggO8 plate slidably surrounding the safety cable 132 and to which is pivoted a brake lever 162 which is inclined with respect to the safety cable and spring pressed to slide on the same when the slider 160 is pulled upwardly along the cable but which automatically brakes and stops the slider when the same is pushed or pulled downwardly along the cable. Therefore, a jumper is free to climb the ladder 2 while pulling the safety slider 160 along the ladder safety cable 132. Should the jumper or any user accidentally fall off the ladder steps, he will automatically be kept from falling down the ladder by the locked slider 160. There are several sliders along ladder safety cable 132 and a few on each of the jumping platform safety cables 138 and 138A. When the jumper reaches the top of the ladder 2, he detaches himself from the slider 160 on the ladder safety cable 132 and attaches his karabiner 158 to a slider 160 on horizontal cable 138 of the high-level jumping platform so as to move along said platform while being safely hitched against accidental fall. When the jumper is on the pad 86 and is ready to jump, the operator or himself opens the karabiner 158 to release the slider.
The operator beside the jumper, who stands on the pad 86, attaches the lower end of a bungee cord 164 to the front ring 154 of the jumping harness 144. The bungee cord 164 is made of several elastic bands for instance, 500 of the same. The bungee cord (see Figures 30, 31 and 34) is folded into two strands with the lower ends of the strands inserted and fixed within a fitting 166 which has an eye 168 which serves to attach the bungee cord to the front ring 154 by means of two karabiners 158 and short straps 170. The lower portion of the bungee cord 164 adjacent the user is wrapped within a cylindrical cushion 172 made of plastic foam covered with a sheeting and which serves to prevent injuries to the jumper by the bungee cord when the jumper oscillates up and down.
Referring to Figures 7, 10, 30 and 31, it is seen that the top end of the bungee cord 164 is attached to a pair of non-elastic pay-out and retrieval cables 174 which are trained on double pulleys 176 which are suspended from a bar 178 fixed to the top end of the ladder. The two cables 174 extend all the way down the ladder 2 and are connected to a pay-out and retrieval system 180 which is carried by the trailer platform 6 as shown in Figure 4 and which will be described hereinafter.
Referring again to Figures 30 and 31, the two cables 174 are used instead of one as a safety measure, one cable being sufficient to resist the stress imposed by the jumping user so that in the event of failure of onè cable, the remaining cable will not break. The double pulley 176 is suspended by a karabiner 158 and a ring 182 from the bar 178, the ring being positioned between two retaining collars 184 fixed by set screws 186. The double pulley block 188 is provided with cable keeper rollers 190 to prevent the cables from jumping off the pulley. The double pulley block 188 is further attached to the top end of the ladder 2 by cable ties 192 so that if the karabiner 158 or ring 182 or bar 178 fail under stress, the pulley block 188 will remain attached to the ladder 2.
Weights 194 are attached to the outer ends of cables 174 in order to stabilize them against lateral swinging during vertical oscillation of the jumper. Each weight 194 is in the form of a cylinder with a throughbore; they are disposed side by side with the two cables 174 extending through the respective weights 194 and attached to a metal clevis 196, the bolt 198 of which passes through the looped upper end 200 of the bungee cord 164. For safety reason~ ltQe9 9Q~ 202 of retaining bolt 198 is locked in place by two right angle cotter pins 204. A collar 206 surrounds the two strands of the bungee cord just below looped end 200. The two weights 194 are attached to the respective cables 174 by retaining a cable 208 folded into a U with its two legs extending through the bores of the respective weights 194 looped below the weights and with the upper ends of the two legs attached together by a clip 210 to form a complete loop with the free ends of the cable 208 respectively attached to the two cables 174 by clips 212. Should one cable 174 break, the two weights will not fall since it will remain attached to the remaining cable.
Referring to Figures 4 and 12 to 14, the inner end of the two pay-out and retrieval cables 174 are connected to the cable pay-out and retrieval system generally indicated at 180 and which comprises a metal plate 216 fixed flat on the platform 6 and at one end of which is mounted a fixed pulley block 218 in which is rotatable, for instance, two sets of five pulleys 220. A pair of double acting hydraulic rams 222 are disposed side by side longitudinally of and over plate 216, the ends of the cylinders of the two rams 222 being retained in a saddle 224 carried by the pulley block 218. A
movable pulley block 226 also carrying two sets of pulleys 227 is attached by pins 228 to the outer end of the pistons rod 230 of the telescopic rams 222. The block 226 is guided for back and forth movement longitudinally of plate 216 by guiding rollers 232 carried by blocks 226 and in rolling engagement with tracks 234 carried by the inside walls of beams 236 upstanding from and fixed to the base plate 216.
Each one of the two pay-out and retrieving cables 174 is trained back and forth on one set of five pulleys in 21099~8 the fixed block 218 and in the movable block 226. The outer ends of the respective cables 174 are attached to base plate 216 by clamps 240 adjacent the fixed pulley block 218. The cables are retained on the respective pulleys by cable keeper rollers 242 and 244 mounted across the pulley block 218 and 226 respectively.
The two rams 222 are double acting and are each connected to a hydraulic fluid supply pipe 246 and to a return pipe (not shown and disposed below pipe 246 in Figure 12) and the supply and return lines are connected to a reversing electrovalve 248 which is combined with a flow control valve.
The reversal valve automatically stops at the end of its stroke when the movable block 226 hits a limit switch 250 or 252. Valve 248 is removably controlled by the operator standing on the jumping platform, in order to adjust the level of the top end of the bungee cord 164; by a suitable electric circuit, he can stop rams 222 at any intermediate position or he can let the rams reach either their fully extended or their fully contracted position where they stop under the action of limit switch 250 or 252 respectively. In the fully extended position of the movable pulley block 226, the top end of bungee cord 164 will be at its highest level just below double pulley 176. By retracting rams 222, the jumper will be brought to ground level after his jump is terminated. For better safety as shown in Figure 10, the jumper may be lowered into an above-ground swimming pool S after the vertical oscillation of the jumper have subsided. It will be noted that when the two reversing valves 248 are in closed position (there being one valve for each ram 222), they block completely entrance and exit of the hydraulic fluid through the lines 246 and consequently the movable pulley block 226 is positively stopped. Therefore, the system is very safe. It 21 0~908 is noted that such a system has been accepted by the safety authorities of the Province of Quebec concerning bungee jumping while such authorities absolutely refuse the use of a winch with a braking system since they consider such a winch not sufficiently safe.
The system 180 is provided, as noted above, with a flow control valve which is set to about 500 pounds, that is, if the hydraulic pressure accidentally falls below such a value the reversing valve automatically closes the supply and return circuits and locks the rams against further extension or contraction.
The cable pay-out and retrieval system 180 takes a minimum of place since for a ram stroke of about 10 feet, each cable 174 will be paid-out or retrieved a length of about 100 feet, therebeing five pulleys in each set, the two cables being trained in parallel for safety purposes.
The low-level jumping platform 120 (see Figures 11, 23 and 24) is also provided with a cable pay-out and retrieval system 18OA which being shorter than the system 180 of the high-level jumping platform, is positioned on the low-level jumping platform itself, otherwise, this system 180A is of the same construction as system 180 and the pay-out cables 174A
connected to the same are trained on double pulleys 176A
carried by a structure 254 above the low-level jumping platform, outwardly of the safety gate, and on one side thereof, as shown, a bungee cord attached to the cables 174A
is of the same type as bungee cord 164, only shorter, and is attached by the means described in Figures 30 and 31.
It is noted that both jumping platforms can be used simultaneously and the oscillating jumpers will not interfere with each other since the jumping points of both platforms are horizontally offset a substantial amount in the plane of the inclination of the ladder and also to a lesser amount, laterally of the ladder as seen by comparison of Figures 19 and 23 wherein the length of the lower platform which protrudes laterally from the ladder is greater than the length of the cross-leg of the higher-level jumping platform which also protrudes laterally of the ladder.
The laterally offset position of the pulleys 176, 176A with respect to the jumping points of the high-level and low-level jumping platforms respectively (see Figure 25) is selected such that there will be no interference between the jumper, the ladder and the guy wires and braces stabilizing the ladder should there develop a horizontal component of movement during the vertical oscillation of the jumper.
The system is very safe. Redundant means have been provided wherever there is a safety hazard. The persons climbing the ladder are constantly attached to the safety cable.
Apart from the operator standing on the jumping platform, only one jumper is allowed on the same for preparation for jumping due to the presence of the safety gates.
The exit safety gate is unlocked only when the jumper stands on the pad 86 or 86A when he is actually ready to jump.
The whole ladder system and components can be easily lowered and folded and positioned on a trailer 8 to be moved to another site and the entire system can be quickly erected.
Referring to Figure 36, there are shown means for catapulting the user up in the air instead of the latter jumping from either platform 74 or 123. The erected ladder 2 is used as shown in Figures 10 and 11 with the addition of a concrete block 256 which is positioned on the ground G
2tO9~08 approximately in line with the swimming pool S looking at Figure 10, and just laterally of one of the outrigger arms 48 and concrete block 62 looking at Figure 11. The user wears a harness 258 and the outer end of the bungee cord 164 is attached to the back of the harness 258 by means of a karabiner 260 removably attached to a ring 262 which is anchored to a block 264 fixed to the back of the harness 258.
A cable link 266 is attached to the concrete block 256 by a cramp 268 and to a ring 270 which is in turn releasably attached to the block 264 and which may be quickly manually released therefrom by a releasing mechanism of any known type in block 264. Finally, a scale 272 is serially connected in the cable link 266, the scale 272 having a read-out display 274 indicating to the operator the pull exerted by the stretched bungee cord 164.
The catapulting system is operated as follows:
using the cable pay-out and retrieval system 180, the non-elastic cable 174 is paid out so as to lower the bungee cord 164 sufficiently for the operator on the ground to grasp the lower end of the bungee cord and attach it to the user A by means of the karabiner 260. The user is then attached to the concrete block 256 by means of the releasable ring 270. The cable pay-out and retrieval system 180 is retracted so as to cause the double cable 174 to stretch the bungee cord 164 in sufficient amount as read on the read-out 274 of the scale 272. Obviously the concrete block 256 must have a weight sufficient to resist the pull of the stretched bungee cord.
Then the operator releases the ring 270 from the block 264 and the user is catapulted or hurled up in the air in a vertical plane which is generally co-planar with the upper end of the ladder 2 but in a vertically inclined trajectory due to the above-noted position of the concrete block 256, thus clearing 21~9908 the upper end of the ladder 2 as well as the guy wires 46.
After oscillation has subsided, the user is gradually lowered to the ground by again lowering the upper end of the bungee cord 164.
FIELD OF THE INVENTION
The present invention relates to an apparatus for oscillating users in a generally vertical plane by means of an elastic cord or bungee cord.
BACKGROUND OF THE INVENTION
Bungee jumping is a sport which has developed in the last decade. The user jumps off a high-level jumping platform being attached to an elastic cable or bungee cord. After his vertical oscillations have subsided, the jumper is lowered to the ground by means of a non-elastic cable attached to the bungee cord and to a winch or the like which serves to pay-out and retrieve the non-elastic cable and the bungee cord. It has been found that known bungee jumping systems lack in safety features with the result that jumpers have accidents.
Known jumping systems are also static structures being intended to be erected and permanently used on one site with the result that after a few seasons, the clientele of jumpers becomes depleted.
OBJEcTs OF THE INVENTION
The general object of the present invention is to provide a bungee jumping system which has a number of safety features to considerably reduce the occurrence of accidents to the jumpers and attending personnel.
Another object of the present invention is to provide a system of the character described which is quickly erected and dismantled and is easily transported from one site to another.
Another object of the invention is to provide a system of the character described further including a ladder provided with two jumping platforms at two different levels to accommodate jumpers of different degrees of bravery, and which ~ 2109908 can be used at the same time to increase the jumping capacity of the system.
Another object of the invention is to provide a bungee jumping system which can also be used for catapulting a user from ground level up in the air.
SUMMARY OF THE INVENTION
The apparatus of the invention serves to oscillate users in a generally vertical plane and comprises an elongated base structure, a ladder made of several ladder sections, releasable securing means to secure said ladder sections in alignment, pivotal means connecting the lower end of the ladder to the base for raising and lowering movement of the ladder in a vertical plane, power means carried by the base structure to raise the ladder to a steeply inclined operative position, a jumping platform secured to the topmost section of the ladder and protruding at an angle thereto and horizontally disposed when the ladder is in operative position, a bungee cord, means to attach one end of the bungee cord to a user, a pulley carried by the top of the ladder above the jumping platform, a non-elastic cable trained on the pulley and attached to the other end of the bungee cord and power operated means to pay-out and retrieve the non-elastic cable between a retracted position adjacent said pulley in which a user attached to said one end of said bungee cord is suspended above ground even when said bungee cord is fully stretched, and an extended position in which said one end of said bungee cord is closer to the ground and allows the attached user to land.
Preferably, the several ladder sections are serially hinged to each other for pivotal movement between an accordeon-like folded position and an unfolded aligned position, the assembly of the sections when unfolded having an ~- 2109908 overall length several times that of the elongated base structure and the assembly of the folded sections having a length generally the same as that of said elongated base structure, which is preferably a wheeled roadable base structure to be towed by a road tractor. The power operated means to pay-out and retrieve the non-elastic cable preferably consists of a double-acting hydraulic ram having a fixed end and a movable end, a fixed assembly of return pulleys at said fixed end of said hydraulic ram, a movable assembly of return lo pulleys carried by the movable end of said hydraulic ram, the non-elastic cable being trained several turns around the return pulleys and fixed at one end adjacent the fixed assembly of pulleys. Shortening and lengthening of the hydraulic ram causing pay-out and retrieving of the non-elastic cable to an amount which is a multiple of the stroke of the hydraulic ram whereby the latter can be installed on the base structure. A flow control valve automatically blocks the hydraulic ram against extension or contraction movement should the oil pressure inadvertently fall below a predetermined level.
The user, while climbing the ladder is always attached to a safety cable running along the ladder by means of a safety slider which allows ladder climbing but prevents falling movement.
Preferably the bungee cord is suspended from a pair of non-elastic cables, each of sufficient force to retain the jumper should the other cable break.
Preferably the jumping platform has safety gates arranged to delimit a jumping area accessible to one jumper at a time, one of the gates closing a ~umping orifice made in the guard rail surrounding the jumping platform, therebeing provided a spring supported pad which is linked to the gates ~4 2109908 so as to unlock one gate while locking the other and which is responsive to the presence of the user on the pad so that the jumping orifice gate is unlocked only when the jumper is standing on the pad ready to jump.
The user wears a harness to which the free end of the bungee cord is removably attached. Preferably the apparatus also includes means to serve to catapult a user from ground level up in the air and to land the user. This catapulting system includes retaining means to temporarily retain the other end of the bungee cord at ground level while the non-elastic cable means is in retracted position with the bungee cord in stretched condition and further including releasing means to release said retaining means to cause the bungee cord to pull the attached user upwardly. Preferably the retaining means includes a weighted block adapted to rest on the ground and link means linking the block to the harness, the releasing means serially connecting the link means to the harness, the block being of a weight sufficient to resist the pull of the stretched bungee cord. Preferably, a scale with a read-out is serially interposed in the link means to indicate the pull exerted by the stretched bungee cord.
BRIEF DESCRIPTION OF THE DRAWINGS
In the annexed drawings, Figure 1 is a side elevation of the bungee jumping system in transport mode;
Figure 2 is a rear end elevation of the same taken along line 2 of Figure 1;
Figure 3 is a partial elevation showing the hinge between two ladder sections and taken along line 3-3 of Figure 2;
Figure 4 is a top plan view of the trailer shown in Figure 1 and showing how the ladder sections are unfolded;
~ 21099~8 Figure 5 is a side elevation of the extended outrigger arm, this view taken along line 5 of Figure 4;
Figure 6 is a cross-section taken along line 6-6 of Figure 2 and showing the ladder raising telescopic hydraulic cylinder in retracted position;
Figure 7 is a side elevation of the ladder assembly in half-raised position on the trailer;
Figure 8 is a partial side elevation on an enlarged scale of one of the two pivotal connections of the ladder to the trailer and taken in area 8 of Figure 7;
Figure 9 is a cross-section taken along line 9-9 of Figure 8;
Figure 10 is a side elevation of the ladder and trailer with the ladder in a fully raised, operative position lS and properly stabilized by guy wires and braces ready to be used;
Figure 11 is an end elevation of the assembly of Figure 10;
Figure 12, seen on the seventh (7th) sheet of drawings, is a cutaway top plan view of the cable pay-out and retrieval system and taken in an area delimited by line 12 in Figure 4;
Figure 13 is a longitudinal section taken along line 13-13 of Figure 12;
Figure 14 is a cross-section taken along line 14-14 of Figure 12;
Figure 15, seen on the sixth (6th) sheet of drawings, shows the connection of a brace to the lower-level jumping platform and taken in area 15 of Figure 11;
Figure 16 is a partial side elevation taken in area 16 of Figure 11 and showing the pivotal connection of the lower end of a ladder brace to the platform;
~ 2109908 Figure 17 is a cross-section taken along line 17-17 of Figure 16;
Figure 18 is a partial elevation on an enlarged scale taken in area 18 of Figure 11 and showing how the top end of the ladder brace is connected to the ladder;
Figure 19, seen on the eighth (8th) sheet of drawings, is a plan section taken along line 19-19 of Figure 11 and showing the high level jumping platform;
Figure 20 is a partial vertical section taken along line 20-20 of Figure 19;
Figure 21 is a vertical cross-section taken along line 21-21 of Figure 19;
Figure 22 is a partial elevation taken along line 22 of Figure 19;
Figure 23 is a plan section taken along line 23-23 of Figure 11 and showing the low level jumping platform;
Figure 24 is a side elevation of the low-level jumping platform;
Figure 25, seen on the ninth (9th) sheet of drawings, is a partial elevation of the ladder and a front end elevation of the low-level jumping platform, and taken along line 25 of Figure 24;
Figure 26 is a partial vertical section taken in area 26 of Figure 22;
Figure 27 is a schematic plan section taken along line 27-27 of Figure 26;
Figure 28 is a partial elevation taken in area 28 of Figure 25;
Figure 29 is a schematic plan view of the system shown in Figure 28;
Figures 30 and 31 are a partial side elevation and a front elevation respectively showing the top end of the ~ 2109~08 ladder, the double pulley, and the attachment of the bungee cord to the pay-out cables, these Figures being taken in area 30 of Figure 7;
Figures 32 and 32A show the jumper harness in side elevation and back elevation and attached to the lower end of the bungee cord;
Figure 33 shows the jumper harness in front elevation while the jumper is oscillating;
Figure 34 is a partial elevation taken in area 34 of Figure 32 and showing the attachment of the lower end of the bungee cord to the harness;
Figure 35 is a partial elevation of the safety cable and safety slider; and Figure 36 is partial elevation of the catapulting system and showing the user about to be catapulted.
In the annexed drawings, like reference characters indicate like elements throughout.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The bungee jumping system comprises a ladder 2 pivoted at its lower end by hinges 4 to a base structure, namely a base platform 6 which forms the top of an elongated roadable trailer 8 mounted on tandem wheels 9 and which is hinged at its front end by a conventional fifth wheel to a driving tractor 10.
Ladder 2, which may have a length of 100 feet, is composed of a trestle-work 12 supporting a series of steps 14 (see ~igure 20) and the climber is protected by longitudinally extending guide rails 16. A low-level jumping platform 18 and a high-level jumping platform 20 are secured to the trestle-work 12 of the ladder. Ladder 2 is made of three ladder sections of substantially equal length namely, a lower section 22, an intermediate section 24 and a top section 26. As shown -~- 210990~
in Figure 4, the three ladder sections are serially hinged to each other by hinges 28 and 30 having their hinge axes normal to the hinge axis of hinge 4 and disposed on opposite sides of ladder section 24. Thus the ladder sections 22, 24 and 26 can be folded and unfolded in accordeon-like manner and in a horizontal plane, laterally of the platform 6 when the sections 22, 24 and 26 are in a horizontal position.
Obviously it is the bottom section 22 which is hinged to platfQrm 6 by the two laterally spaced hinges 4, one of which is shown in Figure 9. Hinges 4 are disposed in the front portion of platform 6. The three modular sections 22, 24 and 26 can thus take a folded position in which the three sections are disposed side by side longitudinally of the platform 6 within the lateral confines of the platform 6.
The ladder sections 22, 24 and 26, once unfolded and positioned in mutual alignment, are locked in this aligned position by bolts and nuts (not shown), the bolts inserted into holes 32 made in the ends of the trestle-work 12 of the respective ladder sections (see Figure 2). The arrangement is such that, in the transport mode, the ladder sections 22, 24 and 26 rest horizontally on the platform 6 of the trailer 8 being shorter than the latter.
A power operated means is provided to raise and lower the ladder 2 between a horizontal position and an operative position in which the ladder is steeply inclined as shown in Figure 10. These means consist of a single-acting, telescopic hydraulic cylinder 34, hinged intermediate the end of its bottom section at 36 below the platform 6 about a horizontal transverse axis. Cylinder 34 extends through an opening 38 made in platform 6 and its top end is pivoted at 40 to the upper end of the bottom ladder section 22.
Stabilizer means are provided to stabilize the ladder in its operative position. The stabilizer means (see Figures 10 and 11) includes concrete blocks 42 which serve as counterweights disposed on the front end of the platform 6, guy wires 44 and 46 which are attached to the top ladder section 26 and to the front end and at the rear end respectively of the platform 6. The stabilizer means further includes laterally extending outrigger arms 48 which laterally extend from the opposite ends of the rear end of platform 6, more specifically as shown in Figures 1, 4 and 5. Each outrigger arm 48 is made of telescopic arm sections 50 which, when in telescoped condition, are stored within a transverse retainer tube 52 fixed to the structure of the trailer 8 underneath the rear end of platform 6 such that the entire outrigger arm 48 is stored within the lateral confines of the trailer. The two outrigger arms 48 are offset with respect to the longitudinal axis of the trailer 8 so that the retainer tubes 52 are disposed side by side behind the tandem wheels 9 of the trailer 8. When extended, the telescopic arms sections 50 are locked in position by pins 54. The outermost arm section 50 carries a ground engaging, vertically adjustable leg 56, each outrigger arm 48 is reinforced against upward movement by a brace 58 and an intermediate vertical strut 60.
Both the brace 58 and strut 60 are connected to the arm sections 50 and to the trailer structure by removable pins so that they can be dismantled and stored longitudinally under the trailer platform 6 within the trailer structure.
The back guy wires 46 are preferably directly attached to the top end of the assembly of the ground engaging leg 56 and also, if found necessary, to a concrete block 62 disposed adjacent leg 56. In practice blocks 62 have been found to be unnecessary.
The stabilizing means further include (see Figures 10 and 11) a pair of rigid braces 64 each secured to the top of bottom ladder section 22 by a connection 66 ~see Figure 18) and attached at their lower end to the platform 6 by a pivotal connection 68 tsee Figure 16). The two braces 64 are downwardly diverging. Obviously, during use, the platform 6 is further stabilized by the conventional jacks 70 normally associated with a trailer and used when the driving tractor 10 is disconnected therefrom.
Figure 10 also shows a stairway 72 to allow users to step up to the platform 6 from ground level. Stairway 72 is a unit which can be disconnected form the platform 6 and stored on the latter for transport of the whole assembly.
Referring to Figures 7, 10, 11, 20 and 21, there is provided a high-level jumping platform 74 which protrudes from the underside of the ladder 2 at an obtuse angle relative to the same such that when the ladder is erected in operative position as shown in Figure 10, it will be horizontal. The jumping platform 74 is an assembly which is removably connected to the top ladder section 26 such that this section can rest flat on the trailer platform 6 when the ladder is in folded transport mode.
The steps 14 together with the guard rails 16 terminate at the platform 74 and the ladder is also provided with a guard rail 76 which has an exit opening 78 formed at the end of the cross-leg 80 of the platform 74 which is L-shaped when shown in plan section (see Figure 19).
A slidable safety gate 82 normally closes the exit opening 78; a second safety gate 84 is disposed at the entrance of the jumping platform at the end of the ladder steps 14.
A pad 86 (see Figures 19, 21, 22, 26 and 27, is horizontally positioned on the platform 74 just inside the exit opening 78. Pad 86 is guided for up and down movement between an upper and a lower position and spring pressed to an upper limit position by a pin and sleeve and coil spring assemblies 88 as shown in Figure 26. When the jumper stands on pad 86, the latter is depressed to its lowermost position and actuates a mechanism which unlocks the exit safety gate 82, SQ that the latter may be opened by an operator standing beside the jumper, and simultaneously locks the entrance safety gate 84 so as to prevent access of the next jumper to the jumping platform while the first jumper is preparing to jump. This locking and unlocking mechanism includes a rod 90 secured to the underside of pad 86 and engageable with a lever 92 which is pivoted intermediate its ends at 94 about a horizontal axis. Rod 90, upon depression of pad 86, causes lever 92 to pivot counterclockwise (see Figure 26) from its full line position to its dotted line position.
Exit safety gate 82 (see Figure 22 and 26) includes a U-shaped tube 96 slidable in sleeves 98 horizontally disposed one below the other and fixed to the guard rail 76.
Similarly, the entrance safety gate 84 includes a U-shaped tube 100 slidable in sleeves 102 which are horizontally disposed and are secured to the guard rail 74 and laterally outwardly protrudes from the same. The lower one of each sleeve 98 and 102 is provided with a nipple 104 secured to and downwardly protruding therefrom. In this nipple is mounted a locking pin 106 which is spring pressed by spring 108 into a position entering sleeve 102 and also a hole 110 made in the tube 100 when said tube is in closed position. This locking arrangement is the same for both safety gates 82 and 84.
-Each locking pin 106 is connected to a pulling rope namely a pulling rope 112 for the U-shaped tube 96 and 114 for U-shaped tube 100. The two pulling ropes are trained on pulleys 116 and are attached to opposite ends of the lever 92.
The spring 108 of the locking pin 106 which is associated with the exit gate 82 is stronger than the spring of the other gate whereby lever 92 is pulled in to the normal position shown in full line in Figure 26 wherein the exit gate 82 is locked when the same is closed and the entrance gate 84 is unlocked.
When the jumper stands on the pad 86, the exit gate becomes unlocked while the entrance gate, when in closed position, is automatically locked.
The ladder 2 is also preferably provided with a low-level jumping platform 120 as shown in Figures 7, 10, 11 and 25. This platform 120 is fixed to the top of the bottom ladder section 22 and laterally extends therefrom. It is in horizontal position when the ladder is in fully erected position as shown in Figure 10. Jumping platform 120 is releasably fixed to an angular framework 122 so that it may be removed such that the ladder in transport mode will not exceed the sides of the trailer 8. AS shown in Figures 10 and 11, the jumping platform 120 is stabilized by a pair of braces 124 which are pivotally connected to the platform 120 and to the trailer platform 6 by connector pins 126 such as shown in Figure 15. Jumping platform 120 has a guard rail 128 on both its longitudinal sides and it has an exit gate 130 (see Figures 24 and 25) and also an entrance gate 131 behind gate 130. The jumping platform 120 has also a pad 86A with a gate locking and unlocking mechanism similar to that just described in connection with the high-level jumping station and which is schematically illustrated in Figures 28 and 29, the only difference between the above described locking mechanism lies in the fact that the lever 92A has a different shape than that of lever 92 while the ropes 116A and 118A are attached to the same end of the lever 92A instead of two opposites ends thereof. Also, the positioning of the pulleys is different.
Here again, supposing the exit gate 130 is closed and locked, the same will become unlocked upon a jumper stepping on pad 86A. Simultaneously the entrance gate 131 will become locked supposing that it is in closed position.
The safety gates are shown as horizontally displaceable so that an operator must manually move the same from closed to opened position and vice versa. However it is possible to incline the sleeves 98 and 102 so that the gates will automatically take a normally closed position.
An important safety feature is the provision of safety cables which runs the whole length of the ladder 2 and along the jumping platforms 74 and 120. A ladder safety cable 132 (see Figures 20 and 25) runs along practically the whole length of the ladder 2 alongside one guard rail 16 being attached at its ends 134 and to the top of guardrail 16 and also below the low-level jumping platform (not shown).
Similarly, the high-level jumping platform is provided with a horizontal cable 138 (see Figures 20 and 22) which is attached at both ends at 140 and at 142 to that one of the guard rails 76 which is closer to cable 132. The low-level jumping platform 120 is provided with a similar cable 138A attached to guard rail 128 at 140A and 142A.
The jumper A (see Figures 32 to 35) wears a jumping harness 144 comprising a torso strap assembly 146, a waist belt 148 and thigh belts 150, connected together by strapping 152 and by front and back metal ring 154 and 156. To the waist belt 148 is attached by means of a strap 157 and of a karabiner 158 a safety slider 160 which consists of a U-shaped 210ggO8 plate slidably surrounding the safety cable 132 and to which is pivoted a brake lever 162 which is inclined with respect to the safety cable and spring pressed to slide on the same when the slider 160 is pulled upwardly along the cable but which automatically brakes and stops the slider when the same is pushed or pulled downwardly along the cable. Therefore, a jumper is free to climb the ladder 2 while pulling the safety slider 160 along the ladder safety cable 132. Should the jumper or any user accidentally fall off the ladder steps, he will automatically be kept from falling down the ladder by the locked slider 160. There are several sliders along ladder safety cable 132 and a few on each of the jumping platform safety cables 138 and 138A. When the jumper reaches the top of the ladder 2, he detaches himself from the slider 160 on the ladder safety cable 132 and attaches his karabiner 158 to a slider 160 on horizontal cable 138 of the high-level jumping platform so as to move along said platform while being safely hitched against accidental fall. When the jumper is on the pad 86 and is ready to jump, the operator or himself opens the karabiner 158 to release the slider.
The operator beside the jumper, who stands on the pad 86, attaches the lower end of a bungee cord 164 to the front ring 154 of the jumping harness 144. The bungee cord 164 is made of several elastic bands for instance, 500 of the same. The bungee cord (see Figures 30, 31 and 34) is folded into two strands with the lower ends of the strands inserted and fixed within a fitting 166 which has an eye 168 which serves to attach the bungee cord to the front ring 154 by means of two karabiners 158 and short straps 170. The lower portion of the bungee cord 164 adjacent the user is wrapped within a cylindrical cushion 172 made of plastic foam covered with a sheeting and which serves to prevent injuries to the jumper by the bungee cord when the jumper oscillates up and down.
Referring to Figures 7, 10, 30 and 31, it is seen that the top end of the bungee cord 164 is attached to a pair of non-elastic pay-out and retrieval cables 174 which are trained on double pulleys 176 which are suspended from a bar 178 fixed to the top end of the ladder. The two cables 174 extend all the way down the ladder 2 and are connected to a pay-out and retrieval system 180 which is carried by the trailer platform 6 as shown in Figure 4 and which will be described hereinafter.
Referring again to Figures 30 and 31, the two cables 174 are used instead of one as a safety measure, one cable being sufficient to resist the stress imposed by the jumping user so that in the event of failure of onè cable, the remaining cable will not break. The double pulley 176 is suspended by a karabiner 158 and a ring 182 from the bar 178, the ring being positioned between two retaining collars 184 fixed by set screws 186. The double pulley block 188 is provided with cable keeper rollers 190 to prevent the cables from jumping off the pulley. The double pulley block 188 is further attached to the top end of the ladder 2 by cable ties 192 so that if the karabiner 158 or ring 182 or bar 178 fail under stress, the pulley block 188 will remain attached to the ladder 2.
Weights 194 are attached to the outer ends of cables 174 in order to stabilize them against lateral swinging during vertical oscillation of the jumper. Each weight 194 is in the form of a cylinder with a throughbore; they are disposed side by side with the two cables 174 extending through the respective weights 194 and attached to a metal clevis 196, the bolt 198 of which passes through the looped upper end 200 of the bungee cord 164. For safety reason~ ltQe9 9Q~ 202 of retaining bolt 198 is locked in place by two right angle cotter pins 204. A collar 206 surrounds the two strands of the bungee cord just below looped end 200. The two weights 194 are attached to the respective cables 174 by retaining a cable 208 folded into a U with its two legs extending through the bores of the respective weights 194 looped below the weights and with the upper ends of the two legs attached together by a clip 210 to form a complete loop with the free ends of the cable 208 respectively attached to the two cables 174 by clips 212. Should one cable 174 break, the two weights will not fall since it will remain attached to the remaining cable.
Referring to Figures 4 and 12 to 14, the inner end of the two pay-out and retrieval cables 174 are connected to the cable pay-out and retrieval system generally indicated at 180 and which comprises a metal plate 216 fixed flat on the platform 6 and at one end of which is mounted a fixed pulley block 218 in which is rotatable, for instance, two sets of five pulleys 220. A pair of double acting hydraulic rams 222 are disposed side by side longitudinally of and over plate 216, the ends of the cylinders of the two rams 222 being retained in a saddle 224 carried by the pulley block 218. A
movable pulley block 226 also carrying two sets of pulleys 227 is attached by pins 228 to the outer end of the pistons rod 230 of the telescopic rams 222. The block 226 is guided for back and forth movement longitudinally of plate 216 by guiding rollers 232 carried by blocks 226 and in rolling engagement with tracks 234 carried by the inside walls of beams 236 upstanding from and fixed to the base plate 216.
Each one of the two pay-out and retrieving cables 174 is trained back and forth on one set of five pulleys in 21099~8 the fixed block 218 and in the movable block 226. The outer ends of the respective cables 174 are attached to base plate 216 by clamps 240 adjacent the fixed pulley block 218. The cables are retained on the respective pulleys by cable keeper rollers 242 and 244 mounted across the pulley block 218 and 226 respectively.
The two rams 222 are double acting and are each connected to a hydraulic fluid supply pipe 246 and to a return pipe (not shown and disposed below pipe 246 in Figure 12) and the supply and return lines are connected to a reversing electrovalve 248 which is combined with a flow control valve.
The reversal valve automatically stops at the end of its stroke when the movable block 226 hits a limit switch 250 or 252. Valve 248 is removably controlled by the operator standing on the jumping platform, in order to adjust the level of the top end of the bungee cord 164; by a suitable electric circuit, he can stop rams 222 at any intermediate position or he can let the rams reach either their fully extended or their fully contracted position where they stop under the action of limit switch 250 or 252 respectively. In the fully extended position of the movable pulley block 226, the top end of bungee cord 164 will be at its highest level just below double pulley 176. By retracting rams 222, the jumper will be brought to ground level after his jump is terminated. For better safety as shown in Figure 10, the jumper may be lowered into an above-ground swimming pool S after the vertical oscillation of the jumper have subsided. It will be noted that when the two reversing valves 248 are in closed position (there being one valve for each ram 222), they block completely entrance and exit of the hydraulic fluid through the lines 246 and consequently the movable pulley block 226 is positively stopped. Therefore, the system is very safe. It 21 0~908 is noted that such a system has been accepted by the safety authorities of the Province of Quebec concerning bungee jumping while such authorities absolutely refuse the use of a winch with a braking system since they consider such a winch not sufficiently safe.
The system 180 is provided, as noted above, with a flow control valve which is set to about 500 pounds, that is, if the hydraulic pressure accidentally falls below such a value the reversing valve automatically closes the supply and return circuits and locks the rams against further extension or contraction.
The cable pay-out and retrieval system 180 takes a minimum of place since for a ram stroke of about 10 feet, each cable 174 will be paid-out or retrieved a length of about 100 feet, therebeing five pulleys in each set, the two cables being trained in parallel for safety purposes.
The low-level jumping platform 120 (see Figures 11, 23 and 24) is also provided with a cable pay-out and retrieval system 18OA which being shorter than the system 180 of the high-level jumping platform, is positioned on the low-level jumping platform itself, otherwise, this system 180A is of the same construction as system 180 and the pay-out cables 174A
connected to the same are trained on double pulleys 176A
carried by a structure 254 above the low-level jumping platform, outwardly of the safety gate, and on one side thereof, as shown, a bungee cord attached to the cables 174A
is of the same type as bungee cord 164, only shorter, and is attached by the means described in Figures 30 and 31.
It is noted that both jumping platforms can be used simultaneously and the oscillating jumpers will not interfere with each other since the jumping points of both platforms are horizontally offset a substantial amount in the plane of the inclination of the ladder and also to a lesser amount, laterally of the ladder as seen by comparison of Figures 19 and 23 wherein the length of the lower platform which protrudes laterally from the ladder is greater than the length of the cross-leg of the higher-level jumping platform which also protrudes laterally of the ladder.
The laterally offset position of the pulleys 176, 176A with respect to the jumping points of the high-level and low-level jumping platforms respectively (see Figure 25) is selected such that there will be no interference between the jumper, the ladder and the guy wires and braces stabilizing the ladder should there develop a horizontal component of movement during the vertical oscillation of the jumper.
The system is very safe. Redundant means have been provided wherever there is a safety hazard. The persons climbing the ladder are constantly attached to the safety cable.
Apart from the operator standing on the jumping platform, only one jumper is allowed on the same for preparation for jumping due to the presence of the safety gates.
The exit safety gate is unlocked only when the jumper stands on the pad 86 or 86A when he is actually ready to jump.
The whole ladder system and components can be easily lowered and folded and positioned on a trailer 8 to be moved to another site and the entire system can be quickly erected.
Referring to Figure 36, there are shown means for catapulting the user up in the air instead of the latter jumping from either platform 74 or 123. The erected ladder 2 is used as shown in Figures 10 and 11 with the addition of a concrete block 256 which is positioned on the ground G
2tO9~08 approximately in line with the swimming pool S looking at Figure 10, and just laterally of one of the outrigger arms 48 and concrete block 62 looking at Figure 11. The user wears a harness 258 and the outer end of the bungee cord 164 is attached to the back of the harness 258 by means of a karabiner 260 removably attached to a ring 262 which is anchored to a block 264 fixed to the back of the harness 258.
A cable link 266 is attached to the concrete block 256 by a cramp 268 and to a ring 270 which is in turn releasably attached to the block 264 and which may be quickly manually released therefrom by a releasing mechanism of any known type in block 264. Finally, a scale 272 is serially connected in the cable link 266, the scale 272 having a read-out display 274 indicating to the operator the pull exerted by the stretched bungee cord 164.
The catapulting system is operated as follows:
using the cable pay-out and retrieval system 180, the non-elastic cable 174 is paid out so as to lower the bungee cord 164 sufficiently for the operator on the ground to grasp the lower end of the bungee cord and attach it to the user A by means of the karabiner 260. The user is then attached to the concrete block 256 by means of the releasable ring 270. The cable pay-out and retrieval system 180 is retracted so as to cause the double cable 174 to stretch the bungee cord 164 in sufficient amount as read on the read-out 274 of the scale 272. Obviously the concrete block 256 must have a weight sufficient to resist the pull of the stretched bungee cord.
Then the operator releases the ring 270 from the block 264 and the user is catapulted or hurled up in the air in a vertical plane which is generally co-planar with the upper end of the ladder 2 but in a vertically inclined trajectory due to the above-noted position of the concrete block 256, thus clearing 21~9908 the upper end of the ladder 2 as well as the guy wires 46.
After oscillation has subsided, the user is gradually lowered to the ground by again lowering the upper end of the bungee cord 164.
Claims (21)
OR PRIVILEGE IS CLAIMED, ARE DEFINED AS FOLLOWS:
1. An apparatus for oscillating a user in a generally vertical plane, comprising an elongated base structure, a ladder made of several ladder sections including a topmost and a lowermost section, releasable securing means to serially secure said sections in alignment to form an assembled ladder, said assembled ladder having several times the length of said base structure, ladder pivot means connecting one end of said lowermost ladder section to one end portion of said base structure for pivotal raising and lowering movement of said lowermost section in a vertical plane, power means carried by said base structure and connected to said lowermost ladder section to raise the assembled ladder to a steeply inclined operative position, a stabilizer means to stabilize against tilting said assembled ladder in operative position, a jumping platform secured to the topmost ladder section and protruding at an angle thereto and horizontally disposed when said assembled ladder is in operative position, a bungee cord, means to attach one end of said bungee cord to a user, a pulley carried by said topmost ladder section above said jumping station, a non-elastic cable means trained on said pulley and attached to the other end of said bungee cord and power operated means to pay out and retrieve said non-elastic cable means between a retracted position adjacent said pulley in which a user attached to said one end of said bungee cord is suspended above ground even when said bungee cord is fully stretched, and an extended position in which said one end of said bungee cord is closer to the ground and allows the attached user to land.
2. An apparatus as defined in claim 1, wherein said base structure is a roadable wheeled structure and wherein said ladder sections are serially hinged to one another for movement between an aligned position and an accordeon-like folded position to rest on said base structure for transport.
3. An apparatus as defined in claim 2, wherein the hinge axes of said ladder sections are parallel to one another but normal to the pivot axis of said ladder pivot means whereby said ladder sections can be folded and unfolded in a horizontal plane and laterally of said base structure.
4. An apparatus as defined in claim 3, wherein said ladder sections, when folded, are disposed side by side and rest on said base structure in a transport position and wherein said ladder pivot means are located on one side of said base structure.
5. An apparatus as defined in claim 4, wherein said power means include a telescopic hydraulic cylinder pivotally connected to said base structure and to said lowermost ladder section at a distance from said ladder pivot means and in longitudinal alignment with the latter, being located on one side of said base structure.
6. An apparatus as defined in claim 5, wherein said stabilizer means includes a pair of telescopic outrigger arms carried by said base structure adjacent to said ladder pivot means and extensible laterally of said base structure and taking a telescoped retracted position lying within the lateral confines of said base structure.
7. An apparatus as defined in claim 6, wherein said stabilizer means further include guy wires attached to the raised ladder and to the outer ends of said outrigger arms when the latter are in extended operative position.
8. An apparatus as defined in claim 1, wherein said jumping platform has an L shape when seen in plan defining a passage leg and a jumping leg, the passage leg protruding from the underside of said ladder, said underside facing towards the ground when the ladder is in operative position.
9. An apparatus as defined in claim 8, wherein said jumping platform is a higher-level jumping platform and further including a lower-level jumping platform secured to the top portion of the lowermost ladder section and protruding horizontally from a lateral side of said ladder when raised, said lateral side being at right angles to said underside.
10. An apparatus as defined in claim 1, wherein said power operated means to pay-out and retrieve said non-elastic cable include a double-acting hydraulic ram having a fixed end and a movable end, a fixed assembly of idle pulleys mounted at said fixed end of said hydraulic ram, a movable assembly of idle pulleys mounted on the movable end of said hydraulic ram, said non-elastic cable fixed at said fixed end of said hydraulic ram and trained for several turns around said pulleys of said fixed and said movable assemblies whereby shortening and lengthening of said hydraulic ram will cause pay-out and retrieval of said non-elastic cable respectively for a length which is a multiple of the stroke of said hydraulic ram.
11. An apparatus as defined in claim 10, further including a flow control valve in the hydraulic circuit of said hydraulic ram to automatically lock said hydraulic ram against extension or shortening if the hydraulic pressure supplied to the same is below a predetermined minimum.
12. An apparatus as defined in claim 11, wherein said minimum is 500 pounds per square inch.
13. An apparatus as defined in claim 1, wherein said ladder has a hand-rail from bottom to top of said ladder and further including a safety cable attached to the top and bottom of said ladder, said safety cable extending along said guide rail and accessible to a user climbing the ladder and further including a safety slider surrounding and slidable along said safety cable and a unidirectional lock carried by said slider and engageable with said safety cable to lock said slider against downward movement along said cable but allowing upward movement of said slider along said safety cable and means to attach said slider to a user climbing said ladder.
14. An apparatus as defined in claim 13, further including a guard rail surrounding said jumping platform and a second safety cable extending within said second guide rail and attached to the same at both ends, one end being close to the attachment point of the first safety cable to the top end of said ladder and a second safety slider in slidable engagement with said second safety cable and similar to said first named safety slider.
15. An apparatus as defined in claim 1, further including a guard rail surrounding said jumping platform and defining a jumping orifice and an entrance orifice in communication with the ladder, a jump-off area on said jumping platform just inside said jumping orifice, a jumping orifice fence and an entrance orifice fence, releasable locking means to normally lock said safety fences in orifice closing position and means responsive to the presence of a user at said jump-off area to unlock said jumping orifice fence and lock said entrance orifice fence.
16. An apparatus as defined in claim 15, wherein said last named means include a horizontally disposed pad located at said jump-off area, spring means to urge said pad in an upper limit position, lever means pivoting upon downward movement of said pad caused by the presence of a user thereon, and cable means connecting said lever means with said locking means.
17. An apparatus as defined in claim 1, wherein there are two non-elastic cables disposed side by side and trained on said pulley and both attached to said bungee cord, each cable capable of resisting the jump of a user suspended by said bungee cord, and further including a pair perforated weights disposed below said pulley and through each of which one of said two cables extends, and a retainer cable forming a U-shaped loop defining two legs extending through the respective weights with their respective ends respectively fixed to the respective cables above said weights whereby the two weights will be retained by one cable should the other cable break.
18. An apparatus as defined in claim 1, further including a harness worn by said user and to which said other end of said bungee cord is attached and further including retaining means to temporarily retain said other end of said bungee cord at ground level while said non-elastic cable is in said retracted position with said bungee cord in stretched condition and releasing means to release said retaining means to cause the bungee cord to pull the attached user upwardly.
19. An apparatus as defined in claim 18, wherein said retaining means includes a weighted block adapted to rest on the ground, link means linking said block to said harness, said releasing means serially connected to said link means and to said harness, said block being of a weight sufficient to resist the pull of the stretched bungee cord.
20. An apparatus as defined in claim 19, further including a tension indicating scale interposed in said link means with a read-out to indicate the pull exerted by the stretched bungee cord.
21. An apparatus as defined in claim 11, further including a harness worn by said user and to which said other end of said bungee cord is attached and further including retaining means to temporarily retain said other end of said bungee cord at ground level while said non-elastic cable means is in said retracted position with said bungee cord in stretched condition and releasing means to release said retaining means to cause said bungee cord to pull the attached user upwardly.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA002109908A CA2109908A1 (en) | 1993-11-24 | 1993-11-24 | Bungee jumping and catapulting apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA002109908A CA2109908A1 (en) | 1993-11-24 | 1993-11-24 | Bungee jumping and catapulting apparatus |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2109908A1 true CA2109908A1 (en) | 1995-05-25 |
Family
ID=4152531
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002109908A Abandoned CA2109908A1 (en) | 1993-11-24 | 1993-11-24 | Bungee jumping and catapulting apparatus |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA2109908A1 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2000006275A1 (en) * | 1998-07-28 | 2000-02-10 | Fun Innovators Nz Limited | Retrieval equipment for deployed bungy |
| US6688663B2 (en) | 1998-07-28 | 2004-02-10 | Fun Innovators Nz Limited | Retrieval equipment for deployed bungy |
| FR2883325A1 (en) * | 2005-03-15 | 2006-09-22 | Andre Fournier | SCALE FOR EQUIPPING A MOBILE STRUCTURE SUCH AS, IN PARTICULAR, LORRY, LORRY EQUIPPED WITH AT LEAST ONE SCALE AS FOLLOWS, AND A CABIN THAT CAN BE INSTALLED ON THE SAME SCALE |
| CN111228753A (en) * | 2020-02-19 | 2020-06-05 | 东莞市护康健康管理有限公司 | Medical drawer type training ladder with folding handrails |
-
1993
- 1993-11-24 CA CA002109908A patent/CA2109908A1/en not_active Abandoned
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2000006275A1 (en) * | 1998-07-28 | 2000-02-10 | Fun Innovators Nz Limited | Retrieval equipment for deployed bungy |
| EP1119399A1 (en) * | 1998-07-28 | 2001-08-01 | Fun Innovators NZ Limited | Retrieval equipment for deployed bungy |
| AU743805B2 (en) * | 1998-07-28 | 2002-02-07 | Queenstown Bungy Limited | Retrieval equipment for deployed bungy |
| US6688663B2 (en) | 1998-07-28 | 2004-02-10 | Fun Innovators Nz Limited | Retrieval equipment for deployed bungy |
| EP1119399A4 (en) * | 1998-07-28 | 2004-07-21 | Fun Innovators Nz Ltd | Retrieval equipment for deployed bungy |
| FR2883325A1 (en) * | 2005-03-15 | 2006-09-22 | Andre Fournier | SCALE FOR EQUIPPING A MOBILE STRUCTURE SUCH AS, IN PARTICULAR, LORRY, LORRY EQUIPPED WITH AT LEAST ONE SCALE AS FOLLOWS, AND A CABIN THAT CAN BE INSTALLED ON THE SAME SCALE |
| CN111228753A (en) * | 2020-02-19 | 2020-06-05 | 东莞市护康健康管理有限公司 | Medical drawer type training ladder with folding handrails |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Discontinued | ||
| FZDE | Discontinued |
Effective date: 19960525 |
|
| FZDE | Discontinued |
Effective date: 19960525 |