The invention relates to an apparatus for muscle stimulation including a motor with two motor-operated drives wherein each of these drives comprises a frame and a stepping plate supported in the frame.
U.S. Pat. No. 3,540,436 A1 discloses such an apparatus. The individual drive is a three-member cam drive with a fully wrap-around cam surface. The manufacture of such a cam however requires special machinery and therefore is expensive to manufacture. In order to prevent a lift-off of the stepping plate, the stepping plate is pulled by a tension spring onto the rotating cam disc. Still, a high lift frequency may lead to lift-off of the stepping plate resulting in chatter noises.
It is therefore the object of the present invention to provide an apparatus for muscle stimulation, which can be operated at low as well as high frequencies.
This object is achieved with an apparatus having the features of the main claim. To this end, each drive is a revolving joint square. In each case, the driven drive member is a crank supported in the frame. Furthermore, in each case, one crank and a stepping plate are pivotally interconnected by a coupling member.
Further features of the invention are defined in subclaims and described in the following description with reference to the schematic drawings:
The motor 20 which is for example screwed to the bottom plate 11 is in the shown embodiment a frequency-controlled three-phase motor. By varying the control frequency of the magnetic field of the motor 20, the speed of the motor 20 can be increased or decreased synchronously with the frequency. The apparatus 10 may also have two motors 20. Then each of the two motors 20 drives one stepping plate 81, 181 by way of a drive 30, 130. The two servomotors 20 may be synchronized with each other.
The individual motor may be a gear drive motor which drives for example directly an integral step-down gearing. The output speed of the gear drive motor, is then for example smaller than the described synchronous motor speed. The step-down gearing is a gear drive with parallel, cross-over or intersecting axes.
Also, the use of one or two DC motors with adjustable speed is possible.
In the arrangement as shown in
In the exemplary embodiment, the two belt pulleys 23, 25 are V-belt rib pulleys 23, 25, wherein the driven pulley 25 has for example 2.2 times the diameter of the drive pulley 23 of the motor. The ribbed V-belt 24 may for example have a steel inlay.
For adjusting the belt tension, the motor 20 may be movable for example in the longitudinal direction of the apparatus 10. The pull means 24 may also be tensioned by means of a self-tensioning arrangement, see
In
The individual drive 30, 130—see
The crank 32, 132 is formed by the drive shaft 41 with an eccentrically arranged bearing mount 42, 142. The input drive shaft 41 which, in accordance with the sectional representation of
The eccentrically arranged bearing mounts 42, 142 are disposed in the exemplary embodiment outside the bearings 43, 44. They may for example be displaced relative to each other in a direction normal to the virtual center line 49 at the drive shaft 41. In the exemplary embodiment, the extremities of the two eccentrically arranged bearing mounts 42, 142 with respect to a rotational phase angle of the drive shaft 41 are displaced by 180°. The length of the individual cranks 32, 132 is the distance between the centerline 49 of the drive shaft 41 and the centerline of the eccentrically arranged bearing mount 42, 142 of the respective coupling drive 30, 130. In the exemplary embodiment shown in
The eccentrically arranged bearing mounts 42, 142 support in the representation of
The stepping plate element 34, 134 is supported on one hand via the connecting member 33, 133 by means of a front stepping plate joint 37, 137 an on the frame 31, 131 by means of a frame pivot joint 38, 138. The frame support joints 38, 138 comprise each a pivot bolt 86, 186 supported in the rear by the rear bearing support (13), for example multipart support flange 83, 183 by means of friction bearing sleeves 85, 185 which consist of POM.
The two stepping plates 81, 181 are arranged axially symmetrically with respect to a vertical longitudinal center plate of the apparatus 10. For example, the constant distance of the two stepping plates 81, 181 from each other is less than 2 millimeters. The individual stepping plate 81, 181 is an at least approximately rectangular plate which consists for example of an aluminum alloy. In the exemplary embodiment, its length is 490 mm, its width is 200 mm and its thickness is 10 mm. Its top side 87, 187 has a recessed surface area onto which a slip-resistant rubber mat 88, 188 is cemented. At the top side 87, 187 of the stepping plates 81, 181 in each case one or several rope ears or hooks may be arranged into which a grommet of a rope provided with a handle may be hooked.
During assembly, for example, first the bearing supports 12, 13 and the motor 20 are mounted onto the base plate 11. The drive shaft 41 is then placed into the front bearing support 12 and a grooved ball bearing 43, 44 is slipped onto the bearing supports 51 from the two shaft ends and in each case secured by means of a locking ring 47. After the mounting of the support plates 53, 153, the grooved ball bearings 52, 152 are slipped onto the eccentrically arranged bearing mounts 42, 142 and secured for example by means of locking rings 58, 158. After sliding in the bearings 55, 155, the stepping plates 81, 181 are put in place. In each case, a flange bolt 59, 159 is inserted and secured for example by a hexagonal unit 61, 161. In the frame 31, 131, the individual stepping plate 81, 181 is secured by means of the bolt 86, 186.
After installation and securing of the belt pulleys 23, 25 and the belt 24, the belt 24 is tensioned for example by a displacement of the motor 20.
During operation of the apparatus 10, the user stands with each foot on one of the stepping plates 81, 181. The motor 20 drives by means of the pull member drive 21 the two coupling drives 30, 130. In this way, with each rotation of the input drive shaft 41, each crank is turned by one turn. The two connecting members 33, 133 are positively actuated by the cranks 32, 132 so that the stepping plate joints 37, 137 are moved up and down from, for example, a neutral start out position. During one rotation of a crank, the respective support plate joint 37, 137 reaches a maximum and a minimum. The overall stroke of the stepping plate joint 37, 137 is for example 7 millimeter. The stroke frequency of the stepping plate 81, 181 is between 3 Hz and 30 Hz.
During the oscillating stroke movement each of the two stepping plates pivots about the frame pivot joint 38, 138. The pivot angle out of the neutral position is for example +/− one angular degree.
The stroke frequency of the stepping plates 81, 181 changes proportionally with the drive speed of the motor 20. In this way, the stimulation of the muscles of the user is influenced.
Such sensors 89 may be arranged in, or on, the frame-side stepping plate support joint 38 as well as at the coupling-side stepping plate support joint 37. The summing signal of the two sensors 89 then is to a large extent independent of the position of the user on the stepping plate 81, 181.
For the evaluation, a control signal depending on the mass or, respectively, the mass moment of inertia of the user may be determined but only after an initial operation of for example 10 seconds.
In order to adjust the eccentricity and consequently the length of the crank 32, the shaft unit 23 is loosened. The eccentric ring 71 can then be steplessly rotated for example on the basis of a scale. When the new crank length is adjusted, the crank unit 73 is again tightened. With a form-locking structure disposed for example between the eccentric ring 71 and the shaft should 72, a step-wise adjustment of the crank length is possible. With an adjustability of the eccentricity of the connecting joint 36, the stroke of the stepping plate 81 is adjustable. In the exemplary embodiment, a stroke adjustment of between two and seven millimeter is possible.
The two drives 30, 130 may have different crank length. To this end, the eccentric rings 71 may be adjusted differently. As a result, the stroke travel of the two stepping plates 81, 181 may be different.
The two drives 30, 130 may also be so adjusted that the phase displacement of the two maxima and/or minima differs from 180 degrees. To this end, the two stepping plates 81, 181 are so adjusted that the maximum of the one stepping plate does not coincide, time wise, with the minimum of the other stepping plate 81, 181. In this case, the drive shaft 41 may be provided with an eccentric weight for mass compensation.
The eccentric ring 71 may also be fixed by means of a rapid clamping arrangement. Herein the eccentric ring 71 may be operated from outside of the apparatus 10 by loosening or clamping of an operating handle. Also, the eccentric adjustment may be performed for example from the outside by means of a tool.
During operation of the apparatus 10 with such a frame- and/or coupling-side stepping plate support arrangement 37, the elastomer body 102, 202 also permits an inclined position of the two metal plates 103, 104, 203, 204 relative to each other up to an angle of, for example, three degrees. The composite body 101, 201 could therefore replace the friction or non-friction bearing support of the stepping plates 81, 181 as shown in.
As shown in
In the arrangement of
The bending line then extends for example parallel to the bottom plate 11.
The screw head 115 may for example be disposed on an arched washer 116 provided with an elongated opening, see
Also, the use of a composite body with an elastomer body and front metal plates with a throughbore instead of the plate spring packets 111 is possible.
At the stepping plate side, the leaf springs 121, 221 are supported at the bottom side of the stepping plates 81, 181, for example, in each case in two guide tracks 123, 223. An adjustment sheet 124 which is adjustable in the longitudinal direction of the stepping plate 81, 181 is pressed onto the leaf spring 121 by means of the guide elements 123 so that the leaf spring position relative to the stepping plate 81, 181 is maintained. By an axial adjustment of the adjustment sheet 124, the spring length of the leaf spring and as a result the spring stiffness can be adjusted. The shorter the spring length, the higher is the stiffness of the support.
Also a multi-layer leaf spring pack may be used. In order to increase the stiffness of the support, two or several leaf springs 121 may also be arranged in parallel relationship.
Such a coupling-side stepping plate arrangement 37 may be combined for example with a frame-side stepping plate support 38 including a composite body 101.
Also, in such an apparatus 10, the crank length and/or the phase angle difference may be adjustable.
The pull member drive 21 may be arranged between the two drives 30, 130. It is also possible to provide a pull member drive 21 for each drive 30, 130. It is also possible not to use any pull member drive 21 for the apparatus 10.
Also combinations of the various exemplary embodiments are possible.
Number | Date | Country | Kind |
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10 2010 012 676.4 | Mar 2010 | DE | national |