U.S. Pat. No. 4,134,583 January 1979 Davidson
Brochure 2013 Myrtha Pools
U.S. Pat. No. 5,702,799 December 1997 Brown et al.
The present invention is in the field of starting assist devices for swimmers in competitive swimming and training.
Backstroke swimmers start their swims in the water with their backs to the swim lane, they put their feet on the pool wall or the timing touch pad should it be installed in front of the wall and they hold themselves up with handles outside the water which are provided by starting blocks. During the start preparation phase they pull themselves up and at the start signal they let go of the handles and push themselves of with their feet. An ideal start has the swimmer, coming out of the water, arching back and diving back into the water in a small as possible “hole” in the water to have the least resistance. After the dive in they kick under water as far as they can before they resurface to continue the swim with their arms and feet. The stronger the start force is, the faster the swimmer starts and the further advanced he or she is compared to other swimmers in the underwater phase.
This movement sequence leads to resulting forces that the swimmer puts forth towards the pool wall or timing touch pad. In the horizontal plane the force is mostly perpendicular and moreover that angle is in control of the swimmer. In the vertical plane however there is an angle to the resulting force that is less than 90 degrees; a typical value would be 60-70 degrees. That means a substantial part of the force, the component parallel to the pool wall or timing touch pad, needs to be led into the pool wall or timing touch pad by friction.
That means swimmers encounter an acute problem of possibly slipping when they prepare for the start and then push off during the start. Therefore the fear of slipping at the critical start time prevents many swimmers from exerting their full potential force during the start which reduces performance in races and training.
Materials with high friction coefficient as described for example in patent U.S. Pat. No. 5,702,799 are successfully used to alleviate some of the fear and improve the start forces, but have only a limited effect.
The problem of the vertical force parallel to the pool wall or timing touch pad has been solved well by a starting assist device for backstroke swimmers as described in U.S. Pat. No. 4,134,583 by Davidson. It provides support to the feet of swimmers during the start of a swim through foot supporting means and means for positioning the foot support means which in a described preferred embodiment is a foot rest in essentially wedge form held by straps. It can be positioned to the height desired by the swimmers and be removed in less than 10 seconds. This device provides the necessary means to lead the vertical parallel force via the straps into the pool deck and thus provide a stable platform for backstroke swimming starts.
Once a swimmer has started, it is important that the starting device is removed quickly within 10 seconds or less to remove the protrusion provided by the foot rest which might injure the swimmer when coming back in the lane for a backstroke turn or which may interfere with the timing touch pad of an automated swim timing system.
In the currently known embodiments the starting device is taken out by hand by people on the pool deck such as swim officials or helpers.
The adjustment of the desired height is performed either through buckles which allow to control the length of the straps or in the case of the embodiment described in the brochure by Myrtha 2013 a bar member is hooked into the openings of a starting block containing several holes to provide closer and further distance from the pool edge, thus making the height of the foot rest adjustable within certain limits.
There are several problems with such embodiments; some of them are listed below:
For removal of the starting assist device a person besides the swimmer is needed to remove it after the swimmer has left. If there is no person besides the swimmer available this makes the use of the device impossible, for example during training. Even if a person is available, if the device does not get removed due to lack of attentiveness, serious issues due to the protrusion as described above can result.
In the case of the Myrtha embodiment a bar member outside the reach of a swimmer in the water of the pool needs to be positioned on a starting block. When help is lacking a swimmer can perceivably adjust the start assist device outside the pool and try the adjustment out in the pool but that is very cumbersome.
In the case of the Davidson embodiment the straps are lengthened or shortened by buckles which is cumbersome as well. In a race or training environment with many swimmers, where every swimmer needs to adjust the position to their individual needs this is a serious shortcoming.
The current invention targets one or more of said problems.
To improve the above described problems the following preferred embodiments of a device are described. The device provides positioning means for the foot rest, for example straps, which are connected to an apparatus outside the pool, preferably on the pool deck, which allows for easy adjustment to the desired height by the swimmer and detection when the swimmer has left to then automatically shorten the straps in order to remove the footrest from the pool or lengthen the straps in order to move the footrest down to the bottom of the pool.
One preferred embodiment provides a winding tube in an enclosure around which the straps of the footrest are wound. The spooling tube contains a torsion spring and is connected to a ratchet with a removable lock. The whole apparatus is securely mounted on the pool deck, for example by being fastened to the starting block, the gutter or bolted into the pool deck.
When a swimmer uses the device he or she opens the lock to free the ratchet, pulls down the foot rest to the individually desired height, thus unwinding the straps and winding up the torsion spring. He or she then closes the lock of the ratchet while holding the footrest and puts his or her feet on the foot rest. The lock in the ratchet prevents any further extension of the straps, thus holding the foot rest in position, as long as the holding force of the feet is stronger than the recoil force of the torsion spring. Then he or she performs a start, exuding full force without the fear of slipping vertically from the pool wall, being supported by the foot rest which is held securely by the locked ratchet. After he or she leaves the foot rest the device detects that the swimmer has left because the holding force vanishes and the recoil force of the torsion spring turns the spooling tube, thus winding up the straps. The spooling tube and the ratchet turn, the lock clicks into the ratchet teeth thus slowing down the winding speed, which is a desired effect. After a few seconds the straps are wound up fully, the foot rest comes to a halt at the outside of the device and is ready for the next swimmer.
Other embodiments of the apparatus contemplated include a motorized winch to control the length of the positioning means. The motor is connected to a power supply and a motor control data processing system with data inputs to control the winding, holding and unwinding of the motor and thus the length of the straps, which in turn controls the position of the foot rest.
The data interface can accept information through manual input or through an electronic data interface which is connected to another, external data processing system such as an automated swimming system or a computer with a meet manager application.
Means to detect the status of the apparatus are arranged and connected to the motor data processing system. They detect if a swimmer is on the device, is starting, has left the device and the position the foot rest.
A means to detect if a swimmer is on the device, is starting or has left the device can be a torque measurement system integrated into the winch to measure holding forces, start forces or if the forces of the swimmer have vanished. Depending on the state, the motor holds when the swimmer is on the device or when the swimmer starts, and moves the positioning means when the device detects that the swimmer has left. Other contemplated embodiments for the detection are force detectors on the foot supporting means or on the positioning means, detectors if the feet of the swimmer are on the foot supporting means or such. Together with the known position of the foot rest the apparatus allows for a meaningful positioning of the foot rest during all states of use.
In other embodiments a person watches and detects if one, several or all swimmers in a pool have left and who gives a signal or several signals to the apparatus or to the plurality of apparatuses to change the position of the foot supporting means once a swimmer, several or all swimmers have left.
Other embodiments use the timing touch pad on the pool wall and the swim timing system to detect when the swimmer has left. One embodiment is that the timing touchpad will be pressed by the perpendicular holding forces and start forces of the swimmer, which will cause the timing touchpad to create a signal. Once the swimmer has left the timing touch pad will cease to create a signal and the attached swim timing system can send a “swimmer has left” signal to the apparatus. Since the swim timing system has knowledge of the start signal as well it is particularly suited to generate a signal to the apparatus that the swimmer has left and that the foot rest can be removed.
Other embodiments infer the detection that the swimmer has left by including the start signal into the apparatus. The external timing system carrying the start signal is connected through the data input to the motor control system or a means to detect the audible start signal and/or a means to detect the visible start signal are connected to the motor control data processing system. Once the start signal is detected, after a delay time (for example 6 seconds), the position of the foot rest is changed. In these embodiments a safety means needs to be employed, for example a weak positioning force of the apparatus or an additional detection mechanism as described above, to ensure that a swimmer who has missed the start signal and is still on the foot rest after the delay time will not be injured or startled by the attempt of the apparatus to position the foot rest.
The process of use of the apparatus begins with the foot rest being out of the way of the swimmer, for example wound up on the pool deck or wound down to the pool bottom. The swimmer approaches the apparatus and either inputs the desired positioning information himself, for example “½ inch below the water surface”, or said information is transmitted from an external data processing system with knowledge who the swimmer is and what positioning value he or she needs. In the next step the motor sets the desired position of the foot rest. The swimmer mounts the foot rest and starts, the detection mechanism detects or the start signal reports to the motor control data information system the mounting state and the start state. During both preceding states the motor holds. Once the swimmer has left, the detection mechanism reports this state to the motor control data processing system or the delay time elapses and with the help of said positioning means the motor moves the foot rest out of the way of the swimmer as described above.
In the case of mounting the device onto starting blocks with a single post there is the possibility that the vertical forces through the straps are not exactly the same by either the swimmer not being perfectly located in the center of the foot rest between the straps or by exuding different forces with the legs. This results in a turning of the device and a vertical slipping of the foot rest on the side with the higher force. To prevent this effect the device can be connected via a bar to a like device next to it, which in essence provides a second mounting point, which leads to stable footrests on both devices. This system can be extended to more than two devices, for example to eight located at the eight lanes of a swimming pool, thus leading to stable mounting of them all.
The wound up position of
A data interface 26 to communicate the information about the individual positioning of the foot rest 11 is connected to the motor control data processing system 25. The data interface can accept information by manual input or through an electronic data interface 27 to another, external data processing system 28 such as an automated swimming system or a computer with a meet manager application via data channels known in the art such as serial data lines, CAN bus, USB, wireless data lines or other embodiments of such data channels, and can display the status of the device for example with LEDs. Thus the positioning information of an individual swimmer can be transmitted to the motor 24 either manually for example by the swimmer or automatically through the connected external data processing system 28.
Means to detect the status of the apparatus are arranged and connected to the motor data processing system. They detect if a swimmer is on the device, is starting, has left the device and the position of the foot supporting means.
A preferred embodiment to detect if a swimmer is on the device, is starting or has left the device is a torque measurement system 29 integrated into the winch as known in the art which detects if the swimmer exudes holding forces, start forces or if the holding forces have vanished. Depending on the state the motor 24 holds when the swimmer is on the device or starts and winds the positioning means 12 when it detected that the swimmer has left. Other contemplated embodiments are force detectors on the foot supporting means 11 or on the positioning means 12, detectors 30 if the feet of the swimmer are on the foot supporting means 11 or such.
Means to detect the position of the foot supporting means 11 such as a step counter in the motor control in conjunction with an end detector of the positioning means 12, a length measurement of the positioning means 12 such as marks in the positioning means or such are connected to the motor control data processing system 25 to allow a meaningful positioning of the foot supporting means 11.
The motor control data processing system 25 takes all the inputs and processes them to control the position of the foot supporting means 11 during the various states of the apparatus. The process starts with the foot supporting means 11 being out of the way of the swimmer, for example wound up on the pool deck or wound down to the pool bottom. The swimmer approaches the apparatus and either inputs the desired positioning information himself or herself into the data interface 26, for example “½ inch below the water surface”, or said information is transmitted from an external data processing system 28 with knowledge who the swimmer is and what positioning value he or she needs. In the next step the motor 24 sets the desired position of the foot supporting means 11. The swimmer mounts the foot supporting means 11, the detection mechanism 29 or 30 detects and reports to the motor control data information system the mounting state. The swimmer starts and the detection mechanism 29 or 30 detects and reports to the motor control data processing system 25 the starting state. During both preceding states the motor 24 holds the foot supporting means 11 steady. Once the swimmer has left, the detection mechanism reports this state to the motor control data processing system 25 and the motor 24 positions with the help of said positioning means 12 the foot supporting means 11 out of the way of the swimmer as described above.
The disclosed embodiments are representative of presently preferred forms of the invention, but are understood to be illustrative rather than definitive of the invention.
Filing Document | Filing Date | Country | Kind |
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PCT/US13/52900 | 7/31/2013 | WO | 00 |