US4822037A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Resistance control system for muscle therapy/exercise/training and strength measurement
Assignee: Digital Kinetics Corp
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Filing: 1987-06-05
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Granted: 1989-04-18
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Expires: 2007-06-05
Abstract
Abstract Motion of a user exercising acts against an electric brake. The current flowing in the coil of the brake is controlled by an electronic circuit in accordance with a specified function from a computer or another electronic circuit.
Inventors
- 👤 Terek Makansi
- 👤 Robert E. Hora
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:04
CPC Classifications
A; A63; A63B; A63B21/00; A63B21/005; A63B21/0056; A63B21/0051; A63B21/0052; A63B21/012; A63B21/015; A63B2220/00; A63B2220/10; A63B2220/13; A63B2220/30; A63B2220/34; A63B2220/40; Y; Y10; Y10S; Y10S482/00; Y10S482/901; Y10S482/902
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
208 words
A machine including a resistance control system for use by an individual comprising: first means disposed for engagement by at least one limb of said individual; electric brake of one of the hysteresis and friction types having a rotor and stator, said brake generates a resistance torque to rotary motion of the rotor proportional to an electrical current flowing in the stator; second means for converting motion imparted to the first means by said individual to cause a rotary motion of the rotor of the brake; third means disposed for receiving a signal proportional to the desired resistance torque of the brake to oppose the motion of the individual; fourth means for measuring the torque exerted by the individual; fifth means for increasing the stator current when the desired torque exceeds the measured torque exerted by the individual by applying a voltage to the stator of the brake that is greater than the voltage necessary to maintain the measured torque in the steady state; and sixth means for removing inductive energy from the stator when the measured torque exerted by the individual exceeds the desired torque by maintaining a reverse voltage thereacross that is greater than the voltage necessary to achieve the measured torque in the steady state.
Claim 2
Dependent Claim
208 words
A machine including a resistance control system for use by an individual comprising: first means disposed for engagement by at least one limb of said individual; electric brake of one of the hysteresis and friction types having a rotor and stator, said brake generates a resistance torque to rotary motion of the rotor proportional to an electrical current flowing in the stator; second means for converting motion imparted to the first means by said individual to cause a rotary motion of the rotor of the brake; third means disposed for receiving a signal proportional to the desired resistance torque of the brake to oppose the motion of the individual; fourth means for measuring the torque exerted by the individual; fifth means for increasing the stator current when the desired torque exceeds the measured torque exerted by the individual by applying a voltage to the stator of the brake that is greater than the voltage necessary to maintain the measured torque in the steady state; and sixth means for removing inductive energy from the stator when the measured torque exerted by the individual exceeds the desired torque by maintaining a reverse voltage thereacross that is greater than the voltage necessary to achieve the measured torque in the steady state.
Claim 3
Dependent Claim
20 words
The machine of claim 1 wherein the third means includes a potentiometer creating a variable voltage level between two limits.
Claim 4
Dependent Claim
19 words
The machine of claim 1 wherein the third means includes a digital computer capable of generating an analog signal.
Claim 5
Dependent Claim
25 words
The machine of claim 1 wherein the fourth means is a voltage level across a resistor connected in series with the coil of the brake.
Claim 6
Dependent Claim
13 words
The machine of claim 1 wherein the fourth means is a pressure transducer.
Claim 7
Dependent Claim
13 words
The machine of claim 1 wherein the fourth means is a strain guage.
Claim 8
Dependent Claim
38 words
The machine of claim 1 wherein the electric brake generates a resistance torque through hysteresis loss within a rotor material repeatedly being reverse magnetized by motion within a magnetic field created by the current flowing in the stator.
Claim 9
Dependent Claim
38 words
The machine of claim 1 wherein the electric brake generates a resistance torque through friction of the rotor and stator brought together by the force generated by the magnetic field created by the current flow in the stator.
Claim 10
Dependent Claim
25 words
The machine of claim 1 wherein the electric brake generates a resistance torque through motion of magnetic particles located between the rotor and the stator.
Claim 11
Dependent Claim
24 words
The machine of claim 1 which further includes seventh means disposed to receive and rectify an AC voltage signal for purposes of supplying power.
Claim 12
Dependent Claim
20 words
The machine of claim 1 further includes eighth means disposed to receive direct current from a direct current power supply.
Claim 13
Dependent Claim
46 words
The machine of claim 1 wherein the fifth means includes: difference means for generating a difference signal proportional to the difference between the signals representative of the desired and measured torque values; and bipolar transistor means disposed to have said difference signal applied to base thereof.
Claim 14
Dependent Claim
46 words
The machine of claim 1 wherein the fifth means includes: difference means for generating a difference signal proportional to the difference between the signals representative of the desired and measured torque values; and Mosfet transistor means disposed to have said difference signal applied to gate thereof.
Claim 15
Dependent Claim
55 words
The machine of claim 1 wherein the fifth means includes: difference means for generating a difference signal proportional to the difference between the signals representative of the desired and measured torque values; and silicon-controlled rectifier means disposed to have said difference signal applied to gate thereof and a rectified AC voltage applied to anode thereof.
Claim 16
Dependent Claim
19 words
The machine of claim 1 wherein the sixth means includes a zener diode connected in parallel with the stator.
Claim 17
Dependent Claim
20 words
The machine of claim 1 wherein the sixth means includes a metal oxide varistor connected in parallel with the stator.
Claim 18
Dependent Claim
46 words
The machine of claim 1, further includes: eighth means for sensing the position of the point of engagement of said at least one limb of the individual; and ninth means coupled to the eighth means for making the desired torque a function of the sensed position.
Claim 19
Dependent Claim
13 words
The machine of claim 17 wherein the ninth means includes a look-up table.
Claim 20
Dependent Claim
19 words
The machine of claim 17 wherein the ninth means includes digital computer capable of reading and generating analog signals.
Claim 21
Dependent Claim
37 words
The machine of claim 1 further includes: tenth means for sensing the speed of the user's motion; and eleventh means coupled to the tenth means for generating the desired torque as a function of the sensed speed.
Claim 22
Dependent Claim
39 words
The machine of claim 20 wherein the eleventh means includes a high gain difference amplifier amplifying the difference between the signals representative of the sensed speed and desired speed such that the desired speed is rarely or insignificantly exceeded.
Claim 23
Dependent Claim
30 words
The machine of claim 20 wherein the eleventh means includes an amplifier with a gain value such that a desired proportionality is realized between the torque and speed of motion.
Claim 24
Dependent Claim
31 words
The machine of claim 20 wherein the eleventh means includes a look-up table such that the desired torque is adjusted to cancel the torque produced by friction in the moving mechanism.
Claim 25
Dependent Claim
20 words
The machine of claim 20 wherein the eleventh means includes a digital computer capable of generating and accepting analog signals.
Claim 26
Dependent Claim
36 words
The machine of claim 1 further includes: twelth means for sensing the acceleration of the user's motion; and thirteenth means coupled to the twelth means generating the desired torque as a function of the sensed acceleration.
Claim 27
Dependent Claim
29 words
The machine of claim 25 wherein the thirteenth means includes a gain stage such that the desired torque is adjusted for inertia of the moving parts of the machine.
Claim 28
Dependent Claim
20 words
The machine of claim 25 wherein the thirteenth means includes a digital computer capable of generating and accepting analog signals.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-04-17 | 1992-10-17 | 1993-04-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-04-17 | 1996-10-17 | 1997-04-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-04-17 | 2000-10-17 | 2001-04-18 | $7700.00 | Window Closed / Lapsed |