Device for launching a snowboarder, skier, waterskier or wakeboarder

This invention relates to a device suitable for the moving of a user in the direction of a jump device. This invention relates in particular to a device for the moving (launching) of a snowboarder, skier, water skier or wake boarder, in the direction of a jump device, such as for example a ramp or kicker.

To date there are four kinds of ways in which a snowboarder, skier, water skier or wake boarder can create speed for a jump. The first is to create speed through an artificial ski or snowboard slope. These slopes are usually built for temporary events with the aid of a scaffold construction and wooden planks on which snow, artificial snow or something similar will be placed. The disadvantage is that the construction or purchases of such slopes are very costly and labour intensive. Also, these slopes can because of their height only be placed outside as they are too high to be built in covered halls.

A second way that is currently used to launch a snowboarder, skier, water skier or wake boarder is by means of a so-called winch, which is fixed set up at the end of the launching trajectory, next to a ramp or kicker. The winch pulls the snowboarder, skier, water skier or wake boarder forward while he's standing on his snowboard, board, skis or whether such.

The snowboarder, skier, water skier or wake boarder holds a handle, rope or similar that is connected to the winch. This handle or rope will be released right before the snowboarder, skier, water skier or wake boarder reaches the ramp or kicker.

The major disadvantage of the winch is that the snowboarder, skier, water skier or wake boarder always has to hold "something" to be launched. Hereby all the forces of the acceleration ends up on his arms. Therefore the snowboarder, skier, water skier or wake boarder will be pulled forward in an unnatural position.

Also the launch speed and acceleration is limited, because the force of acceleration the snowboarder, skier, water skier or wake boarder can handle on his arms is limited.

A third method that is currently used is the so-called actuator with rope loop that is described in the Canadian patent publication CA 1 087 922. With the actuator with rope loop the drive is located at the beginning of the launch trajectory and consists of a motor with a pulley. At the end of the launch process is an idler located which is not driven. There is a closed rope loop over the pulley and idler. This rope loop is not tensioned. The rope loop has a certain length that the snowboarder, skier, water skier or wake boarder can hold the rope loop. Right before the snowboarder, skier, water-skier or wake boarder reaches the ramp or kicker he loosens the rope loop and gets launched. The disadvantage - as with the winch - still remains that the snowboarder, skier, water skier or wake boarder has to hold something to create speed.

A fourth way which is described in the German patent publication DE 25 16 315 relates to a mobile jump installation. In this mobile jump installation, an artificial ski or snowboard slope is realized by lifting a ramp on one side using a crane. The slope can be covered with artificial snow mats or can be provided with real snow. The advantage of this installation is that there is no scaffold construction that has to be built. The major drawback of this installation is that the ramp must be built very sturdy because it's only supported at two points. Moreover, this system is very sensitive to wind and is not used in practice.

The purpose of this invention now is to provide a solution for the above-mentioned problems of the four existing ways to create speed and to provide a device which allows a snowboarder, skier, water skier or wake boarder to launch in a simple way. The target of the invention will be achieved by providing a device suitable for moving a user in the direction of a jump device, whereby the mentioned device comprises a rail system and a vehicle with a tiltable launch platform, wherein the carriage is moveable over the mentioned rail system between an initial position and ending position, wherein the device is provided to, during the displacement of the carriage from the initial position to the ending position, tilt the launch platform from a starting position to a launch position.

In the initial position of the carriage, a launch platform is located in his starting position and the launch platform will extend substantially horizontally. The launch platform tilts during the movement of the carriage to its ending position, gradually around a transition point which is located on the front of the launch platform. Therefore, in the launch position, de rear side of the launch platform will be located higher than the front side. Because the launch platform will be tilted gradually during the movement, the angle of inclination of the launch platform (angle of launch platform) will also increase gradually during the movement.

Preferably, the launch platform will be tilted during the movement in function of the speed and the acceleration of the carriage to compensate the impact of the force of the air resistance and the impact of the force of the inertia of the body of the user as a result of the acceleration.

In a preferred embodiment of the device according to the invention, the mentioned device is provided with driving mechanisms for the displacement of the moveable carriage. For this purpose, the devices preferably comprised electromechanical and. or pneumatic and/or magnetic and/or hydraulic driving mechanisms.

According to a particular embodiment of the device according the invention, this further comprises a disconnecting device provided for the disconnecting of the movable carriage of the driving mechanism.

In a more particular embodiment of the device, the device comprises stoppers (brake device) provided for the immediate stop of the movable carriage. By abruptly stopping the carriage, at the height of its ending position, the user will be launched.

The rail system of the device according to the invention comprises at least one first profile which will extend substantially horizontally. Over this first profile the carriage will move between its initial and ending position.

According to a preferred embodiment of the device according to the invention, the device comprises adjusting means which are provided for the adjusting of the angle of the launching platform between the starting position and the launch position. In the launch position the backside of the launch platform is higher than the front side of the launch platform. The mentioned adjusting means are in particular provided for the progressive adjustment of the angle of the launch platform

In a first preferred embodiment of the device according to the invention, the mentioned launch platform has a hinge shaft at the front, in order that the backside can be pressed upwards by the adjusting means.

In a second preferred embodiment of the device according to the invention, the mentioned launch platform has a hinge shaft at the back, in order that the front side can be pressed downwards by the adjusting means.

According to a preferred embodiment of the device according to the invention, the rail system further comprises a second profile which is established slanted and form at least a part of the adjusting means of the device. Preferably, the position of the hinge shaft determines the position of the second profile. In the case the hinge shaft is located at the front side (first embodiment); the mentioned adjusting means comprises a slanted rail profile that gradually rises (in the direction of the first profile) from the beginning of the device towards the end. In the case the hinge shaft is located at the backside (second embodiment); the mentioned adjusting means comprises a slanted rail profile that gradually runs down from the beginning of the device towards the end.

In a preferred embodiment of the first embodiment, the mentioned adjusting means comprises an electric motor which drives a gear wheel using a reduction, that drives at his turn a tooth rack, that pushes at his turn the launch platform at the back gradually upwards during the launch. In the second embodiment, the mentioned adjusting means comprises an electric motor which drives by means of a reduction a gear wheel, that drives at his turn a tooth rack, that pulls at his turn a movable launch platform (8) in the front gradually downwards during the launch.

In another preferred embodiment of the second embodiment, the mentioned adjusting means comprises a compressed air driven piston or by means of oil pressure, which gradually pushes the launch platform at the back upwards during the launch. In the second embodiment, the mentioned adjusting means comprise a compressed air driven piston or by means of oil pressure, which gradually pulls the launch platform at the front downwards during the launch.

More preferred embodiments of the device according to the invention are listed in the dependent conclusions.

The solution according to the invention consists of the earlier mentioned three existing ways to be replaced by a launching device (catapult). This device comprises a moveable carriage, preferably driven by an electric motor. The moveable carriage launches the uses, for example a: snowboarder, skier, water skier or wake boarder, with an increasing speed to make a jump on a kicker or ramp. The user is standing hereby on a launch platform with an adjustable launch pad angle. The angle of the launch platform will hereby be adjusted automatically in function of the speed and the acceleration of the moveable carriage, to prevent that the snowboarder, skier, water skier or wake boarder would fall from the launch platform by the air resistance or the force from the inertia.

By the use of this launch device (catapult), the problems relating to the technical progress will be solved.

• First, the construction of such a launch device is much cheaper than the construction of a ski or snowboard slope. Furthermore, the launch device (catapult) can be built in covered halls because he is not nearly that big as a ski or snowboard slope.
• Second, by the invention of the catapult, the snowboarder, skier, water skier or wake boarder stands right on the launch platform with his snowboard, skis, wake board or the like, attached to his feet. Hereby the snowboarder, skier, water skier or wake boarder doesn't have to hold a handle, rope loop, rope or the like, so he must not stand in an unnatural position and should not undergo all the tensile forces on his arms.
• Thirdly, by this invention, the snowboarder, skier, water skier or wake boarder can resist much bigger forcer, allowing the launch speed and acceleration to be much higher, comparable with that of a snowboard ramp or ski slope.

An alternative for the movable carriage could be to replace the movable carriage by one conveyor belt or different conveyor belts placed after another. The snowboarder, skier, water skier or wake boarder stands instead of on a launch platform on a conveyor belt and will be launched by the increasing speed of the conveyor belt. Or if it concerns different conveyor belts after another whereby the one has a higher speed after the other, the snow boarder, skier, water skier or wake boarder will be shifted from the one conveyor belt after the other with gaining speed and so also be launched at the end. The disadvantage however, as well with one conveyor belt with increasing speed or with several conveyor belts after each other where one has a higher speed after the other, is however that the snowboarder, skier, water skier or wake boarder stands flat on a conveyor belt and there is no compensation for the air resistance and the inertia force, so that there is a risk that the snowboarder, skier, water skier or wake boarder will be pushed to the back.

To further clarify the features of this invention and to indicate additional advantages and particulars, a more detailed description now follows of the device according to the invention. Let it be clear that nothing in the following description can be interpreted as a limitation of the in the conclusions demanded protection.

In this specification is referred by means of reference numbers to the attached drawings, in which:

• Figure 1: a perspective representation shows of the device in accordance with the invention;
  
  

  Figure 2: a drawing is of the device according to the invention, prepared with a walk-in slope and a ramp or kicker. The device is decorated with top and side protection foam;

• Figure 3: a rear view shows of the device with top and side protection mousse;
• Figure 4: a rear view shows of the device without top and side protection mousse;
• Figure 5: an overview drawing is of all forces acting on the snowboarder, skier, water skier or wake boarder during launch, starting from the starting position (Fig. 5.1), to the middle position (Fig. 5.2) to the launch position (Fig. 5.3);
• Figure 6: an overview chart is of all the forces acting on the snowboarder, skier, water skier or wake boarder. In this graph you can clearly see that at any time (t), the forces to lift and the countervailing force cancel each other out.
• Figure 7: a schematic presentation is of the adjustment of the angle of the launch platform by use of a slant rail;
• Figure 8: an overall drawing is of four positions of the launch platform which is further described: launch platform in the starting position (see detail Fig. 9 and 10), launch platform in the middle position (see detail Fig. 11), launch platform at the height of the contact rail (see detail Fig. 12 and 13) and the launch platform in the launch position (see detail Fig. 14 and 15);
• Figure 9: a detailed representation is of the starting position of the movable carriage in which the launcher is still entirely in a horizontal position;
• Figure 10: a detailed representation is of the jumper cable at the starting position of the movable carriage. The jumper cable holds the bulge around the cable loop so the movable carriage can be pulled ahead;
• Figure 11: a representation is of the middle position of the movable carriage in which the launch platform at the back is already partially raised;
• Figure 12: a representation is of the movable carriage at the height of the contact rail;
• Figure 13: a detailed representation is of the cable jumper, when the movable carriage is located at the height of the contact rail;
• Figure 14: a figure is when the movable carriage hit the oil damper;
• Figure 15: a presentation is whereby the snowboarder, skier, water skier or wake boarder ready is to get launched.

In the detailed description the following reference numerals are used among others:

• movable carriage (1); snowboarder, skier, water skier or wake boarder (2); board or skis (3); ramp or kicker (4); straight rail profile (5); slant rail profile (6); hinge shaft (7); launch platform (8); push arm (9); set of wheels for the straight rail profile (10); set of wheels for the slanted rail profile (11); pulley (12); cable loop (13); electric motor (14); oil damper (15); idler (16); cable jumper (17); cable eye (18); bulge (19); contact rail (20); walk-in slope (21); side protection mousse (22); top protection mousse (23) ; starting position (24); launch position (25); centre of gravity (37); gravity (38); vertical gravity (39); horizontal gravity (40); air resistance (41); inertial force (42); launch platform angle (43); middle of the catapult (45); movable carriage at the height of the contact rail (46); acceleration in m/s² (47); speed in m/s (48); force to lift (50); countervailing force (51); longest arm of the cable jumper (52), shortest arm of the cable jumper (53), elastic shaft of the cable jumper (54)

The device in accordance with this invention is suitable for moving a user, in particular a snowboarder, skier, water skier or wake boarder (2) in the direction of a jump device, such as a ramp or kicker. The device comprises a launch platform (8) which is provided to move with increasing speed over a rail system, and that is lifted gradually during the launch as the speed increases, in order to prevent that the user falls off as a result of the acceleration of the platform (2), and whereby the device includes a braking system to bring the launch platform abruptly to a halt so the user gets launched.

In Fig. 1 is an overall drawing made of the entire launching device (catapult) in accordance with this invention. Because the entire catapult is about 30 meter long, two cuts are made. Section A cuts off a part between the launching part and the middle part of the catapult, and section B cuts off a part between the launching part of the catapult and the middle part. Furthermore, the protection is partially removed. Section C cuts off a part from the top protection mousse (23) and section D cuts of a part from the side protection mousse (22).

The catapult further comprises two rails that run over the entire length of the catapult. The upper rail, the straight rail profile (5), runs horizontally and the lowest rail, the slant rail profile (6), runs slant upwards from the starting position (24) to the launch position (25) of the catapult. The operation of these rails will be further described. On the straight rail profile (5) runs the movable carriage (1), this movable carriage (1) is moved from the initial position in the direction of the ending position.

At this movable carriage (1) is a launch platform (8) attached by use of a hinge shaft (7). On this launch platform (8) a snowboarder, skier, water skier or wake boarder (2) can stand with his board, skis or similar without the holding of a handle or rope to gets launched in the direction of a ramp or kicker to make a jump.

The movable carriage (1) comprises, amongst others, the launch platform (8), a push arm (9), a hinge shaft (7), a set of wheels for the straight rail profile (10), a set of wheels for the slanted rail profile (11), a cable jumper (17), a cable eye (18) and an elastic shaft of the cable jumper (54). The operation thereof will be further described. To compensate the impact of the force of the air resistance and the impact of the strength of the inertia of the body of the snowboarder, skier, water skier or wake boarder by the acceleration, the angle of the launch platform will be adjusted from 0 degrees in starting position (24) of the launch platform to +/- 35 degrees in launch position (25) of the launch platform, the operation and calculation thereof is further described.

The movable carriage (1) is driven by an electric motor (14) with frequency control. The drive of the movable carriage (1) further comprises a pulley (12), an idler (16) and a cable loop (13). The cable loop (13) is mounted to the movable carriage (1) through a cable jumper (17). The cable jumper (17) is activated by a contact rail (20). The operation thereof will be further described.

When the movable carriage (1) is reached at the end of the catapult during the launch, it will be stopped by the oil damper (15). The catapult can be used by a snowboarder, skier, water skier or wake boarder (2) to realize a jump; this in combination with a ramp or a kicker, this setup is further clarified.

In Fig. 2, the catapult is shown in combination with a walk-in slope (21) and a ramp or kicker (4). The movable carriage launches the snowboarder, skier, water skier or wake boarder (2) of the starting position (24) of the catapult to the launch position (25).

In Fig. 3, the catapult is visible from behind where the snowboarder, skier, water skier or wake boarder (2) is standing on the launch platform (8) halfway through the launch.

In Fig. 4, the catapult is visible from behind where the snowboarder, skier, water skier or wake boarder (2) is standing on the launch platform (8) halfway through the launch. The protection, in particular the top mousse and the side mousse, is removed so that the two rails are visible.

In Fig. 5, the launch is schematically represented with the movable carriage (1) to the starting position (24) (Fig. 5.1) with transition to the middle of the catapult (45) (Fig.5.2) to the movable carriage (1) in the launch position, (25) (Fig. 5.3). While launching and moving the movable carriage (1) two forces are created that wants to push the snowboarder, skier, water skier or wake boarder (2) of the launch platform (8):

• First, the air resistance (41); the force of the air resistance (41) is caused by the high speed of the snowboarder, skier, water skier or wake boarder (2) whereby his body and equipment resist against the movement in the air.
• Secondly, the inertial force (42). The acceleration creates a force on the body of the snowboarder, skier, water skier or wake boarder (2). This force is caused by the inertia of the mass of the snowboarder, skier, water skier or wake boarder (2). The sum of these two forces is the force to lift (50). This force to lift (50) wants to push the snowboarder, skier, water skier or wake boarder (2) of the launch platform (8) and a solution should be found for that.

The solution to the above problem is to bring the launch platform (8) progressively at an angle; this is the launch platform angle (43). Therefore the centre of gravity (37) of the snowboarder, skier, water skier or wake boarder (2) is progressively raised resulting in a countervailing force (51).

The countervailing force (51) is determined by the gravity (38) and the launch platform angle (43). From the force of gravity (38) and the launch platform angle (43), the vertical gravity (39) and the horizontal gravity (40) can be calculated. This calculation will be further explained. By the correct choice of the launch platform angle (43) the force to lift (50) can at any time of the launch be compensated by the countervailing force (51).

In Fig. 6, is shown by use of a graph that the force to lift (50) is lifted at any time of the launch by the countervailing force (51), by adjusting the launch platform angle (43). This is achieved by adjusting the launch platform angle (43) at any time (t) of the launch.

Legend:

For the left-hand scale

Acceleration in m/s² (47)

Launch platform angle (43)

For the right-hand scale:

Force to lift (50)

Air resistance (41)

Inertial force (42)

Countervailing force (51)

The launch platform angle (43) can be calculated as follows.

Data:

• Mass (m) of the snowboarder, skier, water skier or wake boarder including his equipment in kg. This assumes an average value: 90 Kg.
• Gravity (Fz): m * 9,81 N of 882,9 N
• Frontal area (A) of the snowboarder, skier, water skier or wake boarder. This assumes an average value: 0,7 m².
• Resistance coefficient (Cw) of the snowboarder, skier, water skier of wake boarder. This assumes an average value based on experiments: 1,2
• Air tightness (R0) in kg/ m³. This assumes an average value during the winter months: 1,2 Kg / m³.
• The acceleration: this is gradually inflated and is known at any time (t)
• The time (t)

Formulas:

• Distance covered (S) = SO + V0*t + ½ a*t²
• Speed (V) = V(0) + a*t
• Air resistance (41): F(air) = A*Cw*R0*V²/2
• Inertia: F (inertia) (42) = m*A
• Force to lift (50) = F (air) + F(inertia)
• Countervailing force (51) = force to lift
• Vertical gravity Fzy = Gravity Fz * cos a
• Horizontal gravity Fzx = Gravity Fz * sin a
• Countervailing force (51) = Horizontal gravity Fzx * cos a

Result:

• Launch platform angle a (43)
• Based on of the data and the formulas, at any point in time (t) the launch platform angle a (43) can be calculated so that the force to lift (50) equal is to the countervailing force (51).

In Fig. 7, the launch is schematically represented with the movable carriage (1) at the starting position (24) with a transition to the middle of the catapult (45) till the movable carriage (1) has come in the launch position (25). It is a diagrammatic representation of the invention of the slant profile rail (6) to gradually adapt the launch platform angle (43) from the launch platform (8), without the help of the drive of an additional motor, compressed air or oil pressure. The energy that's used to adjust the launch platform angle (43) comes from the electrical motor of the catapult itself.

The catapult has two rails. The first rail is a straight rail profile (5) and the second rail is the slant rail profile (6). The straight rail profile (5) is horizontal, and the slant rail profile (6) increases gradually in height of the start position (24) to the launch position (25).

On top of the movable carriage (1) is the launching platform (8) attached in scissors shape by use of the hinge shaft (7). At the movable carriage (1) is the set of wheels for the straight rail profile (10) attached, this set of wheels is running in the straight rail profile (5). At the rear of the launch platform (8) is a push arm (9) attached, and to this push arm (9) is the set of wheels for the slanted rail profile (11) attached, this set of wheels is running in the slant rail profile (6).

At the starting position (24) the launch platform (8) is horizontal. As soon as the movable carriage (1) is pulled forward by the pulley, the slant rail profile (6) presses the push arm (9) at the back gradually to height, which pushes, on his turn, the launch platform (8) upwards.

The more the movable carriage (1) moves and the speed increases, and the movable carriage (1) is further and further pulled in the direction of the launch position (25) the slanted rail profile (6) presses the push arm (9) at the back constantly higher, so that the launch platform angle (43) gradually increases.

The advantage of this solution is that the launch platform angle (43) from the launch platform (8) mechanically increases by the tensile force of the motor and the pulley; thereby no additional electrical, pneumatic or hydraulic drive is needed on the launch platform (8) to change the launch platform angle (43).

Another advantage is that the launching platform angle (43) can be set precisely at each position of the movable carriage (1) on the catapult. This with a very low risk of mistakes or failure because there is no mechanical, electrical or pneumatic system needed to realize this launch platform angle (43).

Another possibility is to place the hinge shaft at the rear of the launch platform and to lower the slanted rail profile instead of to rise. This way the front of the launch platform drops as the movable carriage is drawn further and further, making the launch platform angle gradually bigger.

In Fig. 8, an overview is shown of the four positions of the movable carriage which will be further described in detail drawings.

At the start of the launch the movable carriage is in the starting position (24) (see Fig. 9 and 10).

The movable carriage is then pulled forward, and when it has reached the middle of the catapult (45) the launch platform angle is already bigger (see Fig. 11).

Before the movable carriage reaches the launch position (25) it should be disconnected from the cable loop, this will be further described. This separation occurs when the movable carriage is at the height of the contact rail (46) (see Fig. 12 and 13).

At the launch position (25) the movable carriage is brought to a standstill by use of the oil damper, which is further described (see Fig.14 and 15).

In Fig. 9 the movable carriage (1) is in the starting position (24) at the beginning of the catapult ready for the launch. The launch platform (8) is entirely horizontal so the snowboarder, skier, water skier or wake boarder (2) can easily stand up, ready for the launch. The launch platform (8) is horizontal because the slanted rail profile is not pressing (6) the push arm (9) up. The longest arm of the cable jumper (52) is downwards, this can be realized based of its weight, or by use of the elastic shaft of the cable jumper, or the combination of both. Because the longest arm of the cable jumper (52) is down, the shortest arm of the cable jumper (53) clamps the cable loop (13) for the bulge (see detail Fig. 10)

In Fig. 10 a detail is shown from the cable jumper (17) when the movable carriage is in the starting position.

At the starting position, the shortest arm of the cable jumper (53) is pushed upwardly by the elastic shaft of the cable jumper (54) or because the longest arm of the cable jumper (52) is hanging down by its weight, or by a combination of both forces.

The shortest arm of the cable jumper (53) encloses the cable loop (13) and in the cable loop (13) is a thickening or bulge (19). This bulge (19) may consist of a knot or a piece of metal or plastic that is attached to the cable loop (13).

At the start positioning, this thickening (19) is located between the cable eye (18) and the shortest arm of the cable jumper (53).

At the start of the launch, the pulley pulls at to the cable loop (13), thereby presses the bulge (19) against the shortest arm of the cable jumper (53) through which the movable carriage is running ahead.

In Fig. 11, the movable carriage (1) can be seen in the central position. The launch platform (8) at the back is already partly pushed upwards because the slant rail profile (6) is higher than in the starting position. Hereby the push arm (9) is pushed upwards. The cable jumper (17) encloses the cable loop and the bulge so that the cable loop (13) can pull the movable carriage (1) ahead.

In Fig. 12, the movable carriage (1) can be seen at the height of the contact rail (20). When the movable carriage (1) touches the oil damper (15) at the launch position (see Fig. 14 and 15), the movable carriage (1) suddenly stops, this while the electrical motor (14) and the pulley (12) who're driving the movable car (1) yet are able to run out. This is due to the inertia of the electrical motor (14) and the pulley (12), it is impossible for them to stop spinning when the movable carriage (1) hits the oil damper (15), this would lead to breakage. Therefore, the movable carriage (1), at the time that he reaches the oil damper (15) may NOT be attached anymore to the cable loop (13).

The solution designed for this is, to disconnect the movable carriage (1) from the cable loop (13) before the movable carriage (1) has come to the launch position. When the movable carriage (1) reached at height of the contact rail (20) the contact rail (20) will then press the longest arm of the cable jumper (52) upward, hereby, the shortest arm of the cable jumper (53) goes downward and let loose of the cable loop and bulge (see detail Fig. 13). As a result, the movable carriage (1) is no longer connected to the cable loop (13) when the movable carriage (1), the oil damper (15) reaches, this way, the motor (14), pulley (12) and the idler can run further ahead until they come to a rest, without breakage or tension.

Fig. 13 is a detail drawing of the cable jumper (17) when the movable trolley is the height of the contact rail (20). When the movable carriage the contact rail (20) reaches, the contact rail (20) then presses the longest arm of the cable jumper (52) upwards, this way the shortest arm of the cable jumper (53) goes downward and let go of the cable loop (13) and the bulge (19). This allows the cable loop (13) to run further out.

In Fig. 14, the movable carriage (1) can be seen in the launch position (25) when the movable carriage (1), touches the oil damper (15). When the movable carriage (1), the oil damper (15) touches, the contact rail (20) has already pushed the cable jumper (17) upward, and the cable jumper (17), has already released the bulge (19). This allows the electrical motor (14), pulley (12), cable loop (13) and idler to run further out. The movable carriage (1) comes to a complete stop at the oil damper (15).

In Fig. 15

At the launch position (25), the movable carriage (1) comes abruptly to a stop against the oil damper (15). Through the impact of the movable carriage (1) against the oil damper (15), the snowboarder, skier, water skier or wake boarder flies (2) away from the launch platform (8) and he can realize a jump on the ramp or kicker, via the walk-in slope (21)

At the end of the launch, the pulley rotates slowly in the opposite direction. This brings the bulge back until it presses to the cable eye. The pulley then pulls the movable carriage (1) back.

When the movable carriage (1) comes at the end of the contact rail, the cable jumper is automatically re-energized by its own weight and/or by the elastic shaft of the cable jumper. The pulley pulls the movable carriage then further back up to the starting position and the movable carriage (1) is then ready for the next launch.

The great advantage of the jumper cable is that this mechanism works fully mechanical. There is no electrical, hydraulic or pneumatic drive necessary to disconnect the movable carriage (1) from the cable. This results in a robust and reliable system that can withstand the high speed, acceleration and forces which are released from the impact of the movable carriage (1) against the oil damper (15).