Loading device for physiological examinations

[54] LOADING DEVICE FOR PHYSIOLOGICAL EXAMINATIONS [75] Inventor: Jézsef Csekes, Debrecen, Hungary [73] Assignee: Medicor Muvek, Budapest, Hungary [21] Appl. No.: 371,301 [22] PCT Filed: Aug. 28, 1981 [86] PCT No.: PC!‘/HU81/00034 § 371 Date: Apr. 12, 1982 § 102(e) Date: Apr. 12, 1982 [87] PCT Pub. No.: W082/00769 PCT Pub. Date: Mar. 18, 1982 [30] Foreign Application Priority Data Aug. 29, 1980 [HU] Hungary ............................ .. 2131/80 [51] Int. Cl.3 ...................... .. A63B 21/24; H02K 7/10 [52] U.S. Cl. .................................... .. 272/73; 272/129; 310/ 75 B [58] Field of Search .................. .. 272/73, 129; 73/379;

[56] References Cited U.S. PATENT DOCUMENTS 2,195,328 3/1940 Eaton .............................. .. 310/75 B 4,084,810 4/1978 Forsman .......................... 272/73 FOREIGN PATENT DOCUMENTS 244166 5/1969 U.S.S.R. .............................. .. 272/73

Primary Examiner—Robert A. Hafer
Assistant Examiner—Arnold W. Kramer
Attorney, Agent, or Firm—Anthony H. Handal

[57] ABSTRACT

Physiological loading device having a central pedal drive shaft 5 which drives via a freewheel a drumshaped wheel 21 with inner gearing to which are advantageously coupled three follower gears. These drive, via gearing, an inner shaft 10 which is arranged around the drive shaft. The rotor of an electric rotational motor is arranged at the inner shaft, the rotor being surrounded by an armature 4 with poly-phase winding. The armature 4 is located between an inner and an outer housing part. The rotor windings are supplied with energizing current from sliding contacts, and the armature windings are connected to a braking unit.

3 Claims, 2 Drawing Figures

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LOADING DEVICE FOR PHYSIOLOGICAL
EXAMINATIONS

The invention relates to a loading or stress-inducing device for physiological examinations, which device has a shaft driven by the person to be examined, a drive with a free wheel, a transmission gear, a fly wheel mass which is coupled with the acceleration side of the transmission gear, a follower electric motor in brake operation and to which are connected externally electrical control and loading circuits.

In a physician’s practice increasingly examination methods are used in which not only static but also dynamic values are determined under load. The dynamic values play an important role in the prophylatic and rehabilitation diagnostics, as well as in general, sports related or work related medical diagnostics. The load or stress is advantageously produced by pedaling or bicycling which subjects old or young or experienced as well as inexperienced patients to the same load. The bicycling can be accomplished either lying down or standing up.

The general demands made upon loading or stressinducing systems are: variable loading, no harmful effects, interruption at random and, they must be physiological and reproducible.

A special advantage is a feedback if the loading system can be controlled by the functional parameters, such as breathing, EKG, blood pressure, etc. On the basis of present knowledge the following technical solutions are used for producing the load: eddy current brake, electric motor in brake operation, a dynamomotor-tachometer system, scale motor, mechanical braking, etc. The disadvantages of the above mentioned variations are; a sturdy structure, high production cost, large basic friction, force or restraining systems due to the characteristics of rotational machines, high current consumption, and loading that is dependent on the number of revolutions.

Of several known physiological loading units those distributed by MEDICOR-WERKE (unit KE21) shouldbe mentioned. In this unit via a pedal drive and by means of a free wheel, a fly wheel mass and finally an electric motor of a specific structure is driven in brake operation. The electro-motor is connected to external control and loading circuits by means of which" the desired load is adjusted, that is, the compensation for internal friction is accomplished, which may amount to 40 to 50 watts. The heretofore known devices are, although they perform their basic function, disadvantageous in that they are too heavy so that their handling and transport is made difficult and in that for compensating for the interior friction extensive solutions are required whose accuracy is not always sufficient.

It is, therefore, an object of the present invention to produce a physiological loading unit of the type mentioned above which is simple in structure and has a small inner friction.

The physiological loading unit according to the present invention comprises a shaft driven by the person to be examined, said shaft being provided with a free wheel, a transmission gear, a fly wheel mass which is coupled to the acceleration side of the transmission gear or with an electro motor in brake operation. External electrical control and loading circuits are connected to the electro motor. Furthermore, the drive shaft is connected via a free wheel to a drum wheel with internal

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gearing and the interior of which is provided with several intermediate gears of equal size and with equal number of teeth and which are evenly distributed along a circle. The intermediate gears are coupled to a pinion which is arranged on the drive shaft. The rotor of the electro motor is arranged on the internal shaft so that it simultaneously forms the fly wheel mass. The stator of the electro motor is located next to the drum wheel with interior gearing and carries a polyphase winding which is connected to the electric loading circuit. Furthermore, the rotor windings are connected to the external control circuit by means of sliding contacts. In order to achieve a better utilization of space the rotor is designed such that the iron core consists of two overlapping halves which are bent towards each other. In the space between the two halves the fly wheel mass and the rotor windings are located. _

In an advantageous embodiment according to the present invention, the stator consists of an inner and an outer housing part as well as of an armature which is arranged between the same and connected by threaded spindles. The shafts of the follower gears are connected to the inner housing part.

The invention is illustrated, by way of example, in the accompanying drawings, in which:

FIG. 1 is a composite of the physiological loading device, half in side view and half in section;

FIG. 2 is a section taken along line II—II of FIG. 1.

The physiological loading or stress-inducing device illustrated in FIG. 1 comprises a stator and a rotor connected thereto. The stator consists of a drum-shaped outer housing 1 which has an inner space, and of an inner housing 3 which is held by threaded spindles 2. A laminated armature 4 is arranged between the inner and outer housing 1, 3. The armature comprises crenellated spools and has a three-phase winding.

In the interior of. the stator there is provided centrally a drive shaft 5 which is journalled in bearings 6, 7. The drive shaft 5 extends on both sides beyond the sidewalls and carries respective pedals 8 and 9. The drive shaft 5 is surrounded by an inner shaft 10 which is not directly coupled to the drive shaft 5 and which is journalled in a bearing 11 in the outer housing 1 and a bearing 12 in the inner housing 3.

The inner shaft 10 has on both sides a shoulder which is respectively confined by iron yokes 13, 14. The iron yokes 13, 14 are disc-shaped and are bent towards each other at their ends in the manner of .a comb so that they form magnetic cores. In the space between the iron yokes 13, 14 there is located the fly wheel mass 15, the surrounding wound spool 16 and the rotor windings 17. The terminals of the windings of the rotor 17 are connected to sliding rings 18 and from which the carbon brushes 19 connected to the outer housing 1 receive the current. The rotor is driven by the pedals 8, 9 via the. drive shaft 5. This drive shaft 5 is coupled via a free wheel 20 to a drum wheel 21. The free wheel 20 brings about that the drum wheel 21 receives a torque in one direction only so that no braking action is exerted onto the drum wheel 21 during rotation when the pedals are temporarily at a standstill.

FIG. 2 shows in section the acceleration transmission gearing, arranged between the drum wheel 21 and the inner shaft 10. The drum wheel is provided with gear teeth along it inner margin. The gear teeth mesh with three follower pinions 22, 23, 24. These pinions are light plastic gears the supporting shafts of which are journalled at the inner housing 3. FIG. 1 shows the follower