BE1018032A3 - Fall protection system for rock or wall climber, uses rotating permanent magnets and eddy current recordable plate for providing controlled braking in cable drum - Google Patents

Abstract

The system uses rotating permanent magnets and eddy current recordable plate for providing controlled braking in a cable drum.

Description

MAGNETIC FALL PROTECTION

Position of the field

In situations where there is a risk of falling, it is customary to secure persons to a fixed anchor point by means of a climbing belt (safety belt or harness) and via a climbing rope (lariyard) and a connector (carabiner or musketon). If vertical movement is required, such as rock or wall climbing, ladder climbing, etc., the anchor point must also move up or down. Therefore, the climbing rope is attached to a fall protection cable; the cable will always be tensioned during climbing or descending, but will follow the climber without resistance. In the event of a fall, a brake is applied and the person is braked and brought down with limited speed.

Auto-belav rock climbing devices and modular elimbing towers

Document Type and Number:

United States Patent 6390952 s:

Bates, Jr. et WAVE MOTION COMPENSATING DEVICE FOR

y USE WITH FLOATING HOISTING SYSTEMS

4252214 Miller 182/8 Safety descent device 4449716 Goldyetal. 482/43 Training device forathletes 4941548 Blanchard Fall arresting device for climbers 4997064 Motte et al. Device for automatically securing a climate climbing a wall 5092587 Ulneretal. Climbing System 5125877 Brewer Simulated climbing wall 5254058 Savigny Artificial climbing wall with modular rough surface 5256116 Robinson Climbing equipment 5543185 Christensen Artificial rock climbing structure and method of making 5593368 Checketts Device for reducing impact and lateral movement on resesient surfaces 5695432 Soderlund 482/69 Arrangement for praetizing walking

Terms used

Person: a man or woman, both adult and child.

Fixed anchor point: is a place where cable or rope is supported to the surface. This can be a scaffolding, steel construction, building, pole or tree.

Safety line: is a means with a certain cross-section, such as a tube, a rod, a rail, a rope or a cable. The safety line can run over several fixed anchor points.

Mobile anchor point: is formed by a carabiner over a safety line

Carabiner: A musketon, also called carabiner, is a metal hook with a twist or snap closure. This is one of the most important and universal accessories for climbing. From a safety point of view, musketons that are used as 'single point of failure' are often equipped with a safety mechanism to prevent unintended opening.

Climbing belt: A climbing belt or simply belt is used when climbing and descending to create a stable attachment point to the human body.

Lanyard: Is the flexible connection by means of a rope, cable or ribbon between the movable anchor point and the safety belt. In the invention, a person is secured by a climbing belt, lanyard, and carabiner.

Magnetic induction:

If an electrical conductor moves in an alternating magnetic field, a current is induced in the conductor. This principle is used in all engines and alternators. This current also generates a magnetic field that opposes the applied magnetic field.

Eddy currents: Foucault currents or Foucault currents are electric currents that are intentionally or unintentionally induced in a (flat) conductor. It is a physical phenomenon that occurs when, for example, a variable magnetic field is present in a metal plate (not necessarily ferromagnetic). This can be an alternating field of an electric coil but also a movement in which the field lines are cut through the plate. When a conductor intersects magnetic field lines, a current is induced in that conductor. This current is short-circuited by the conductive plate. The braking force is generated by the generation of an electric current in the aluminum disk because this conductor moves in an alternating magnetic field. Eddy currents are the basis of this brake.

Parachute jump: In the simulation of a parachute jump, the person stands on a high tower and will jump into thin air. In the beginning, the fall speed will increase, but as the ground approaches, the speed must slow down to an acceptable level (+/- 2 m / s) So the protection must have a variable braking force.

decelerator after command cable (zip Une):

If a cable or rope is tensioned from a higher point to a lower point, the person can move downwards via a pulley. Depending on the length and steepness, the speed can be very high here. 50 km / h is no exception. If the necessary measures are not taken at the end, the person may be seriously injured when stopping. So a "fall protection" is also needed here. There are currently various techniques in use for this braking (springs, elastics, buffers, etc.) but this invention can be used perfectly for this. The version with steerable braking force is suitable for this so that the first contact would not be too abrupt. A short phase without deceleration would be needed to get the brake up to speed; this already substantially inhibits the descent. From then on the brake will brake harder progressively.

In practice, it comes down to mounting an extra shuttle on the cable at the start of the braking process. This shuttle is connected to the magnetic brake. The moment the person collides with the shuttle in the descent, the brake starts to roll; first with little resistance, until the brake has sufficient speed, then gradually to maximum braking force.

Speed limiter: When going down a command line (zip line) the speed can be very high. The invention can be adapted such that the brake gradually brakes more as the speed increases.

Air gap: This term is used to indicate the distance between the aluminum disc and the magnetic poles.

Cable reel: The steel cable is wound onto the cable reel or cable drum to which the person is protected

Constant braking force:

A certain force is required to slow down a person during a fall. This slows down the movement.

Steerable braking power:

If the braking force may not always be the same, it is necessary to have a check on the braking force. This is done with a controller that adjusts the braking force.

Helix: A part of the cable reel is provided with a very coarse thread, even coarser than a corkscrew; better comparable to the angled s of a drill. This thread is called helix.

Description of the invention

In general, the invention is used for recreational purposes, but industrial applications are also possible. The invention can be realized in various embodiments: 1) constant braking force 2) steerable braking force.

1: constant braking force

The cable reel contains sufficient cable for the height to be protected. A winding spring is mounted herein to rewind the cable after unrolling. The entire structure is strong enough to support the weight of the person as well as the reaction forces that occur during the fall.

A thick aluminum disc is mechanically coupled to the axis of the cable reel by means of a helix with coarse pitch. Magnets are positioned next to the aluminum plate. A (weak) neutral position spring pushes the disc away from the magnets, so that few lines of communication through the; aluminum plate. In this situation the cable can unwind freely. Rolling up also happens without any noticeable resistance, although the brake here already limits the maximum rolling speed.

If the person falls, a much greater force will act on the cable. This causes the aluminum disk to be driven towards the magnets by the inertia against the spring force. The helix still supports this. The aluminum disk is now in the maximum range of the field lines, so that the generated foucault currents now provide maximum braking power. The air gap is now minimal. The speed is now determined by the balance between braking force and weight. An additional small-range load spring will now keep the aluminum disk a few mm further away from the magnets if a less heavy person is braked, so that the downward speed will be approximately the same for light or heavy people.

Once the person has arrived on the ground, the force on the cable becomes small and the spring will push the aluminum disc away from the magnets. The foucault currents have disappeared when the aluminum disc has stopped.

If the cable is now released, it will roll up due to the coil spring, but the laying speed will still be limited because the influence of the magnets still has an effect on the aluminum disc. So the foucault flows also limit the roll-up speed.

2: variable braking force.

The invention is also suitable for this, provided that an additional control can dose the braking force. For this a variable stop is mounted on the shaft that is moved left or right with a fine thread.

The stop keeps the aluminum disc away from the magnets in the initial phase so that the person rushes down in free fall. As the cable reel unrolls, the stop is screwed away with the fine thread. Over time, the aluminum disk has come very close to the magnets so that the braking force is now maximum. The stop no longer limits the aluminum disk so that from now on the situation occurs with the "constant braking force".

After disconnecting, the cable is wound up again as previously described

Claims (10)

1. A new fall protection mechanism through the introduction of the use of permanent magnets and rotating eddy currents receiving plate. 2. An improved fall mechanism without rubbing parts. By using eddy current there is no wear to the brake components. 3. Improving the safety of fall protection. Moisture, dirt and grease do not influence the braking force. 4. An improvement in the reliability of fall protection due to the absence of frictional parts. 5. An improvement in the maintenance of fall protection. There are no typical wear parts present. 6. An improvement in the lifetime of the fall protection. The permanent magnets and the rotating eddy current receiving plate are passive components. 7. An improvement in the adjustability of fall protection. By varying the air gap a progressive brake is created that is too adjustable without external energy. 8. A renewal through the universal use of the magnetic brake for multiple applications., ...., Due to the separation of the functions of each subsection, the brake can be adapted to many different situations and operating conditions. One version can be used for both zipline and parachute jump. 9. A renewal by the construction method. The brake is very compact and can be built lighter than existing systems. 10. An improvement in comfort: the descent speed during the fall of a light person and a heavy person is now largely the same. Wikipedia sources