The invention relates to an ergometer, preferably a bicycle ergometer, comprising a pedal arrangement which is mounted in a frame and an adjustable braking device which optionally acts on a disk flywheel.
Bicycle ergometers have recently found a wide field of applications. They are thus used, in addition to private use, both in medicine, especially in sports medicine for the purpose of performance diagnostics, as well as for checking the training progress in competitive sports. Further fields of application are in rehabilitation, e.g. for accident and stroke patients.
From DE 36 03 853 A1 a bicycle ergometer with a pedal arrangement has become known which comprises an adjustable braking device and a display instrument for the braking torque. In the zone of the handlebar grips there is a panel which comprises an indicator for the torque and speed. The user of the ergometer is thus provided with information about the torque required for overcoming the set braking force and the respectively achieved speed.
An ergometer is further known from DE 42 27 586 A1 which is used for finding and training the optimal sequence of movements. The device can be used to detect constructive and destructive force elements which are released by a cyclist on the pedals in real time and under real training conditions. For this purpose the elastic deformations relevant on the pedal lever as well as the deformations of handlebar and seat post are detected in a selective fashion and in a manner independent of each other by means of a suitable arrangement of wire resistance strain gauges. The obtained data allow determining and optimizing the complete sequence of movements of the cyclist, which means that the force components which are converted into the forward movement can be maximized and force components which cannot be converted into forward movement because they produce a static counter-force for example are minimized. It is disadvantageous that the apparatus is relatively complex because up to four possible elastic deformations (flexion in the direction of rotation, flexion perpendicular thereto, elongation in the longitudinal direction of the pedal lever, torsion about the longitudinal axis of the pedal lever) need to be detected and evaluated separately and independently from each other.
A further class of bicycle ergometers is used in medical diagnostics for the purpose of determining the aerobic/anaerobic threshold of a patient, with the performance being gradually increased and various data of the patient such as heart rate, O2 and CO2 content of the respiratory air, etc. being determined. Such ergometers have become known from U.S. Pat. No. 4,463,764 A and U.S. Pat. No. 5,782,772 A for example.
It is disadvantageous that the known apparatuses are incapable of determining differences in the pedaling behavior of the left and right leg of a test subject as uninfluenced as possible from any disturbances and with high resolution within a crank rotation.
It is the object of the present invention, based on an ergometer of the kind mentioned above, to provide improvements which allow detecting the torque progress of each crank or each leg separately with high resolution within a rotation of the crank.
This object is achieved in such a way that the two pedals of the pedal arrangement are mounted independently of each other, excluding the transmission of force from one pedal to another. Furthermore, a separate braking device is provided for each pedal whose braking force can be controlled independent from each other. Whereas in conventional ergometers both pedals are fastened to a continuous crank axle, it is possible as a result of the complete mechanical separation of the power flux of both pedals to detect their torque progress depending on the crank angle independent from each other and, after preparation in a computer unit, to transmit the same to a display device in the field of vision of the training person or the patient in rehabilitation.
For this purpose it is provided for in accordance with the invention that a torque sensor and/or a tachometer generator are situated on the crank axle of each pedal which is in connection with a computer unit plus display device, preferably a monitor. With the data of the sensors on the crank axles it is possible to display on the monitor a torque or force/angle curve of the respective leg. This feedback system can be used by the cyclist to directly or indirectly influence his or her turning behavior in order to reduce lateral differences and consciously work on his or her evenness on both sides.
The fields of application of the ergometer in accordance with the invention are mainly in two fields:
In accordance with the invention, each of the two auxiliary motors can comprise an anti-spasm control unit which can be activated automatically during the occurrence of a sudden change in resistance. When a patient uses an ergometer where pedaling is supported by an auxiliary motor it is advantageous when the motor cuts off during the occurrence of spasms (suddenly occurring, excessive muscular tone) or changes the direction of rotation. This helps prevent that the spastic limb is moved by the auxiliary motor by force.
The force separation in the crank drive of the ergometer can be produced according to an embodiment of the invention in such a way that one of the pedals comprises a crank axle with a tubular projection and the other pedal a crank axle with a cylindrical projection, with the cylindrical projection being rotatably held in the tubular projection. For applications as a conventional bicycle ergometer the two projections may comprise mutually flush radial bores. By inserting a fixing screw into the radial bores, the pedal arrangement can be fixed in a 180° geometry.
The invention is now explained in closer detail by reference to the enclosed drawings, wherein:
The ergometer schematically shown in
The chain wheel 19 is fastened to a flange 21 on the crank axle 7′ or 8′ with the help of an adapter disk 20. The chain guard is designated on both sides with reference numeral 22. The torque sensor consists for example of a torsion ring 23 which is fastened to the crank axles 7′ or 8′ and which co-operates with a data sensor 24 which is preferably fixed to the chain guard 22. The signal line starting from the data sensor 24 and leading to the computer unit 6 is designated with reference numeral 25.
Number | Date | Country | Kind |
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GM 462/00 | Jun 2000 | AT | national |
Filing Document | Filing Date | Country | Kind |
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PCT/AT01/00198 | 6/21/2001 | WO |