RU1806800C - Pedal mechanism - Google Patents

Abstract

Use of the invention: in devices for providing a metered load on a human limb during rehabilitation or prophylactic traction / forging. SUMMARY OF THE INVENTION: The pedal mechanism comprises a hollow body. The housing is mounted on the drum half shaft. The axles of the satellites of the sun gear are fixed in the drum. The sun gear is installed along the axis of the coaxial half shaft of the drum. Cranks of variable length are fixed on the axis of the sun gear, which are connected by means of a telescope to telescopic rods with pedals. Telescopic connecting rods mounted on the semi-axle x. On the inner surface of the housing there is a ring gear for the satellites. 3 s.p. f-s, -3 ill.

Description

 The invention relates to medical equipment, and in particular to devices for providing a metered load on a finite device. STI during rehabilitation or preventive training.

The aim of the invention is to provide the possibility of individually dosing the load on various muscle groups of the limbs by changing the shape and orientation of the trajectory of their movement during training.

In FIG. 1 provides a diagram of the pedal mechanism; Fig. 2 is a diagram for calculating a path; Fig. 3 shows variations in the orientation and shape of the path of movement of the pedals.

The pedal mechanism comprises a movable housing 1 mounted on the hollow axis 2 of the drum 3, in which the axles 4 of the satellites 5 are fixed, which engage with the sun gear 6 fixed on the axis 7,

mounted coaxially with the hollow axis 2. On the axis 7 are fixed cranks 8 of variable length connected by rods 9 with telescopic connecting rods 10 equipped with pedals 11. Telescopic connecting rods 10 are mounted on the hollow axis 12. The crown gear 13 is made on the inner surface of the housing 1, engages with the satellites 5, On the outer surface of the housing 1 is made a gear 14, which engages with a set gear 15, kinematically connected to the control unit 16 and equipped with a handle 17 with a scale mechanism 18. On the hollow axis 2 CREPLA drive sprocket 19 which is kinematically coupled to the brake assembly 20.

The pedal mechanism works as follows.

When rotating the pedals with 11 legs or hands, the length of the telescopic connecting rod 1P

00

about

smiling

With

oh oh

will be changed by rotation of the crank 8 of variable length with a string 9. The planetary gear transmission, consisting of a drum 3 with satellites 4, a sun 6 and a coronary gear 13, is designed so that its gear ratio can take only two values: - 1 and +3. Only at the indicated values of the gear ratio the pedal paths will be closed curves - ovals.

Using figure 2 with simple trigonometric transformations it is possible to obtain a formula defining an oval trajectory of pedals, as follows:.:.

With a small A, it is approximately equal

(7)

Cos / 3 «1 - (1 -Co $ 2 p. (8)

Then

10

Sn-r (1 -Cos) 1

(9)

fifteen

In polar coordinates, S4 will be expressed as

) 1 t; . t

CD (2)

where a is the angular speed of rotation of the crank 8;

"G is the angular velocity of rotation of the telescopic connecting rod 10:

t - current time ..

Denote the gear ratio of the planetary gear by

1 . OD

(3)

and the ratio of the length of the crank to the length of the rod through

 L A-, (4)

Substituted the value of I 1 in (3), (2), can be converted

  -a t --- (5) p - 2 a. (6)

Using trigonometric transformations, the length of the telescopic connecting rod 10 can be expressed in rectangular coordinates

 (1 + J) -rx X -Cosip + 2 (1 -Cos /) 1 r rCosp + Cos / .. (7) 1

p r cos2 a - Sin2 a + j | l - 2 H2 (cos2 a - Cos4 a) +

twenty

(10)

5

0

5

5

0

5

Formula (10) is an equation for the movement of pedals 11 along an oval path. With a change in the parameters g, A and m, it is possible to set the desired shape of the trajectory of the pedals (Fig. 3).

Similarly, the equation of motion of the pedals 11 can be obtained for a planetary gear ratio of -K. ,. ; . . :

Thus, to change the shape of the oval paths of the limbs that drive the pedal 11, it is enough to change the length of the crank 8 or the distance from the axis of the rod 9 to the pedal 11. To change the position of the axes of the oval path of the pedals 11, it’s enough to change the initial angle "o (Fig. H), turning the housing 1 using the handle 17 on the scale mechanism 18 to a fixed position, or in accordance with a given law using the control unit 16. The control unit can be made, for example, in the form of a low-power low-speed electric motor controlled by programmable timer.

Depending on the type of trained muscle groups of the extremities, the length of the crank 8, the position of the housing 1 using the handle 17 according to the scale mechanism 18 and the load of the brake assembly 19 are pre-set. The brake assembly can be made in the form of a set of friction disks with a normalized value of the braking torque and with the ability to adjust it. If necessary, changes in the configuration of the trajectory according to a given law include the control unit 16. The patient drives the pedal 11 with the help of arms or legs. In the case of training with the legs, the patient is in the seed position, while the load unit is fixed on the floor. If it is necessary to train the limbs in a circular path, the rod 9 is turned off, and the telescopic connecting rod 10 is fixed in a certain position.

The invention allows for patient training with the possibility of individual dosing of both the load value and the shape and orientation of the limb trajectory.

The proposed load unit can be used both in low-ergometers and exercise bikes, as well as in devices for mechanotherapy.

Claims (4)

1. A pedal mechanism comprising a cranked lever carrying two telescopic connecting rods, a planetary gear train and means of transmitting motion from the planetary gear to the connecting rods to provide the possibility of reciprocating movement of the latter, characterized in that, in order to increase the efficiency of use, the transmission means of movement is made in the form of a rotatably mounted housing, a drum placed in the housing by means of hollow semi-axes and two cranks with variable length, and the planetary gear transmission is made in the form of a sun gear, rigidly installed on the axis of the drum half-axis coaxially located, two satellites whose axes are mounted on the drum, and a ring gear located on the inner surface of the housing, In this case, variable-length cranks are rigidly mounted on the axis of the sun wheel and are associated with one of the telescopic rods, telescopic rods are mounted on the drum axles, and the link of the cranks and rods is made in the form of t. 2. The mechanism according to claim 1, with the exception that the gear ratio of the planetary gear train is (-1) or (3). 3. The mechanism according to claim 1, about t and h and y u and with the fact that it has a brake unit, and on an asterisk is mounted on one of the semiaxes, while the sprocket is kinematically connected with brake unit. 4. The mechanism according to claims 1 to 3, with the exception of the fact that it has a control unit kinematically connected with the housing, this kinematic connection is made in the form of a gear located on the outer surface of the housing, and entering into the engagement of the mounting gear having a gear mechanism and connected to control unit. Fig j  FIG. 2.