AU711530B3 - Apparatus for providing resistive forces - Google Patents

Description

AUSTRALIA

PATENTS ACT 1990

ORIGINAL

COMPLETE SPECIFICATION PETTY PATENT Invention Title: APPARATUS FOR PROVIDING RESISTIVE FORCES Name of Applicant: ALI JADIDI The following statement is a full description of this invention, including the best method of performing it known to me/us: 2 APPARATUS FOR PROVIDING RESISTIVE FORCES Field of the Invention The present invention relates broadly to an apparatus for providing resistive forces during an exercise, particularly, but not exclusively to simulate the resistive forces which may occur in a natural environment. The invention will be described herein with reference to a cycling exercise device, but has applications to other types of exercise device, such as a rowing exercise device.

Background of the Invention In exercise devices or virtual reality devices it is often desired to simulate a natural environment in which a certain activity would normally be performed. Such exercise devices include treadmills, stepping machines, stationary cycling machines, rowing exercise devices.

In order to simulate the natural environment such as variable degrees of inclination or varying wind resistance, the exercise device must have mechanisms to alter the resistive force which needs to be overcome at different stages during the exercise in order to produce the impression of resistance varying with variations in the "natural environment". For example, there are now treadmills available which can change the inclination of the running/walking platform during the exercise to simulate different inclination on a natural running track.

The present invention provides an alternative to existing mechanisms.

Summary of the Invention In accordance with a first aspect of the present invention there is provided an apparatus for providing a resistive force during an exercise comprising actuator means arranged to, in use, have an actuating force applied to it by a person exercising on the apparatus; pneumatic means associated with the actuator means for providing the resistive force; load adjusting means for adjusting a pneumatic load of the pneumatic means; and control means for, in use, controlling the load adjusting J:\Speci\300 399\300 349\34104.doc 3 means to controllably adjust the load of the pneumatic means based on control data.

Preferably, the control data comprises simulation data for simulating a natural environment in which the exercise is supposed to be performed. For example, the load of the pneumatic means may be controlled to simulate, in one embodiment, an uphill portion of a cycling track during an exercise on a stationary cycling machine.

Preferably, the apparatus further comprises means for measuring a pressure in the pneumatic means.

Accordingly, the actuating force applied by the person can be readily determined.

Advantageously, the control data comprises data based on a signal generated by the means for measuring the pressure, to provide a feed back from the pneumatic means during the controlling of the load adjusting means.

In one embodiment, the load adjusting means comprises a valve. Preferably, the valve comprises a ball valve.

Advantageously, the ball valve is adjustable by means of a stepping motor.

In one embodiment, the means for measuring the pressure comprises a strain gauge type pressure transducer.

Advantageously, the actuator means comprises a crank shaft.

In one embodiment, the pneumatic means comprises pistons, the pistons being rotatably connected to the crank shaft.

In another embodiment, the actuator means comprises a lever mechanism.

The apparatus may further comprise a fan, the fan being arranged in a manner such that its speed can be varied continuously.

In one embodiment, the speed of the fan is controlled through a pulsed supply signal of variable frequency, which primes a stepping up transformer which provides a power supply for the fan.

In another embodiment, the control means is arranged to effect a reduction of the load of the pneumatic means in J:\Speci\300 399\300 349\34104.doc -4response to an input made by the person to reduce a gear ratio of the actuator means.

In accordance with a second aspect of the present invention, there is provided an exercise device comprising an apparatus for providing a resistive force during an exercise comprising actuator means arranged to, in use, have an actuating force applied to it by a person using the apparatus; pneumatic means associated with the actuator means; load adjusting means for adjusting a pneumatic load io of the pneumatic means; and control means for, in use, controlling the load adjusting means to controllably adjust the load of the pneumatic means based on control data.

Preferred forms of the invention will now be described, by way of example only, with reference to the accompanying drawings.

Brief Description of the Drawings Figure 1 shows a schematic side view of an exercise device in accordance with one embodiment of the present invention.

Figure 2 is a schematic drawing of one component of the exercise device of Figure 1.

Figure 3 is a schematic top view of a detail of Figure 1i.

Detailed Description of the Preferred Embodiments In Figure 1, the exercise cycle 10 includes a rear sprocket 12 which is connected to a crank shaft 14. The crank shaft 14 has two pistons 16, 18 rotatably connected to it, with the pistons 16, 18 being movably inserted into hollow pump cylinders 20, 22, respectively. The cylinders 20, 22 are pivotally connected to an axle 24 mounted on the frame 26 of the cycle 10. The pistons 16, 18 and cylinders 22 form part of two air pumps 28, 30, which suck air through valves (not shown) of the piston plates 32, 34 when the pistons 16, 18 move in the direction 36, and which pump air through hoses 41, 43 connected to the cylinders 20, 22, respectively, when the pistons 16, 18 move in the direction J:\Speci\300 399\300 349\34104.doc 37. Hoses 41, 43 form a further part of the air pumps 28, Turning now to Figure 2, the hoses 41, 43 terminate in enlarged, rigid end portions 46, 48. Pressure monitors 42, 44 are provided at the end portions 46, 48, respectively.

The pressure monitors 42, 44 measure an internal pressure in the end portions 46, 48, which is correlated with the internal pressures in cylinders 20, 22 (see Figure 1) In the embodiment illustrated in Figure 2, the pressure monitors 42, 44 are strain gauge type pressure transducers, and an output signal from the monitors 42, 44 is transmitted for subsequent processing by a computer 52 (see Figure 1) The signals from the monitors 42, 44 are analysed by the computer 52. The computer 52 can also transmit control signals to a stepping motor The stepping motor 60 is coupled to two ball valves 62, 64 inthe end portions 46, 48, respectively. By varying the volumetric flow rate of the valves 62, 64, a pumping resistance for the pistons 16, 18 (see Figure 1) can be varied.

If the volumetric flow rate of the valves 62, 64 is reduced, a larger force is required to move the pistons 16, 18 in the direction 37 (see Figure 1) at a given speed, due to an increased internal pressure in the pumps 28, respectively.

In the computer 52, the output signal from the monitors 42, 44 can be correlated with the setting of the ball valves 62, 64, which is controlled by the computer 52 through the stepping motor On the computer 52, software is installed which is used to simulate a cycle ride. One of a number of different preset cycle courses may be selected. Each cycle course includes characteristic profiles such as the contour of the course variation in the inclination of a course, turns etc.) J:\Speci\300 399\300 3 49\34104.doc 6 The course profile can be displayed on a screen connected to the computer 52.

In a natural environment, changes in the contour result in changes in a resistive force against which the cyclist has to work, for example changes from a level portion to an uphill portion result in an increas.e of the resistive force. This increase in the "environmental" resistive forces can be simulated with the exercise device To simulate e.g. an increased resistive force, the volumetric flow rate of the valves 62, 64 for air discharge 61 through the open ends 63, 65 of pump 30, 28, respectively is reduced.

Due to the reduction of the volumetric flow rate, the pressure load) against which the pumping action in the direction 37 will occur (see Figure 1) will increase.

The changing of a gear can also be simulated by altering a piston area a in a formula to calculate the internal pressure p required to simulate a particular resistive force f: p=f a (200) If the gear ratio is e.g. changed by a factor of 2 to a smaller ratio, the (resistive) internal pressure required would be reduced to one half of its initial value.

Returning now to Figure i, the computer 52 can be used for a large variety of functions including for example the analysis of a counter input from a speedometer 70. Further signals can be received through monitors (not shown) to detect turning, breaking, tilting of the cycle 10. Further input signals could be received by the computer 52 such as measurements of the cyclist's heart beats.

The cycle 10 further comprises a fan 72, which is controlled by the computer 52. The speed of the fan 72 is varied through a pulsed supply signal of variable frequency, which primes a stepping up transformer which provides the power supply to the fan 72. Thereby, the J:\Speci\300 399\300 349\34I04.doc 7 speed of the fan 72 can be continuously varied to more realistically simulate changes in a wind resistance during the exercise.

Within the computer 52, the various signals received can be used to calculate simulation data on the basis of which the resistive force load in the pumps 28, (Figure 2) is controlled, and on the basis of which the position and velocity of the cyclist can be determined at any point.

From the above it will become apparent how all other physical forces dictated by the environment at a particular position can be considered by a computer program to control the resistive pressure in the pumps 28, 30 (Figures 1 and 2) and to then incorporate the physical effect of the pedalling effort by the cyclist to determine the cyclist's position within the environment.

It will be appreciated by a person skilled in the art that numerous variations and/or modifications may be made to the present invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects to be illustrative and not restrictive.

In the claims that follow and in the summary of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprising" is used in the sense of "including", i.e. the features specified may be associated with further features in various embodiments of the invention.

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Claims (3)

1. An apparatus for providing a resistive force during an exercise comprising actuator means arranged to, in use, have an actuating force applied to it by a person exercising on the apparatus; pneumatic means associated with the actuator means for providing the resistive force; load adjusting means for adjusting a pneumatic load of the pneumatic means; and control means for, in use, controlling the load adjusting means to controllably adjust the load of the pneumatic means based on control data.

2. An apparatus as claimed in claim 1 wherein the control data comprises simulation data for simulating a natural environment in which the exercise is supposed to be performed.

3. An apparatus as claimed in claims 1 or 2, wherein the apparatus further comprises means for measuring a pressure in the pneumatic means to determine a force applied by the person. Dated this 30th day of August 1999 Ali Jadidi By his Patent Attorneys GRIFFITH HACK J:\Speci\300 399\300 3 4 9 3

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