Patent Application
20100022924
I. Field of the Invention
The present invention relates generally to physical therapy devices and, more particularly, to a physical therapy vibratory table.
II. Description of Material Art
It is well known that during extended periods of inactivity, muscle atrophies and loses its muscle tone. As a result, after extended periods of inactivity, such muscles become very weak and require physical therapy in order to regain the muscle tone and muscle strength.
For example, it is known that astronauts who spend extended periods of time in outer space lose muscle tone through their body due to loss of gravity while in space. In order to prevent, or at least lessen, muscle atrophy, a physical therapy vibratory platform has been previously developed. This previously known physical therapy vibratory table includes a base with a platform supported above the base by rubber bushings. A vibratory motor is attached to the platform so that, upon activation of the motor, the motor vibrates the platform at one or more vibratory speeds.
The vibratory assembly for creating the vibration of the platform for these previously known physical therapy devices, however, has been rudimentary in construction. Typically, the vibratory assembly consisted of little more than a motor with an offset weight attached to the motor shaft. Consequently, rotation of the offset weight by the motor creates an unbalanced load which results in the transmission of vibration to the platform. Some of these previously known devices include two or even more of the motors.
The physically known vibratory tables for physical therapy, however, all suffer from two primary disadvantages. First, the vibration created by the vibratory assembly and imparted to the platform included movement of the platform in not only a vertical direction, but also a horizontal direction. In practice, the vertical direction of vibration for the platform produces the desired therapeutic result for the rehabilitation patient. Conversely, lateral or horizontal vibration of the platform may induce undesirable stress in the joints of the therapy patient. Such stress may damage or injure the joints after prolonged use.
A still further disadvantage of the previously known vibratory platforms for therapeutic use is that the amplitude of the vertical vibration was fixed and could not be altered to vary the vertical travel of the vibratory platform between a lower and upper limit. For therapeutic uses, however, it would be highly desirable to vary the vertical amplitude of the vibration to not only accommodate different patients with different physical characteristics, but also to provide the correct amount of vertical amplitude for the vibration for the physical treatment or therapy of a particular patient.
The present invention provides a vibratory table for physical therapy which overcomes the above-mentioned disadvantages of the previously known devices.
In brief, the vibratory table of the present invention comprises a base and a platform movably supported above the base. Preferably, pneumatically filled bladders support the platform above the base, although other support means may be used without deviation from the spirit or scope of the invention.
A vibratory assembly is also provided to vibrate the platform relative to the base substantially only in a vertical direction. This vibratory assembly includes a roller support that is secured to the platform by any conventional means. A first and second driveshaft are then rotatably mounted to the roller support so that the first and second shafts are spaced apart and parallel to each other.
A mechanical coupler arrangement then connects the first shaft to the second shaft so that the first and second shafts rotate in synchronism with each other and in opposite rotational directions. Preferably, meshing gears form the mechanical coupler arrangement.
A first roller is disposed over the first shaft and, similarly, a second roller is disposed over the second shaft. Each roller is fixed against rotation with respect to its associated shaft but is movable along a predefined radial direction with respect to its associated shaft. Movement of the roller along the predefined radial direction offsets the axis of the roller relative to the shaft axis along that predefined radial direction.
A bladder is disposed in each roller so that the bladder is positioned in between each roller and its associated shaft. Inflation or deflation of the bladders thus displaces the rollers along the predefined radial direction in an amount dependent upon the inflation of the bladder. Preferably, the bladder is pneumatically inflated.
A motor is rotatably drivingly connected to at least one of the shafts. Thus, upon activation of the motor, the rotation of one shaft rotatably drives the other shaft in the opposite rotational direction and so that the rotational position of the shafts are in synchronism with each other.
Inflation of the bladder will thus move the axes of the rollers away from the axes of the shafts and create an unbalanced load. This unbalanced load in turn results in vibration which is transmitted to the vibratory platform.
In practice, the synchronized rotation of the rollers in the opposite rotational directions by the mechanical coupler arrangement is sufficient to eliminate horizontal movement of the vibratory platform since the horizontal force imparted by each roller on the platform is offset by the other roller. Similarly, the vertical amplitude of the vibratory platform may be varied by increasing or decreasing the inflation of the bladders as desired. Increased inflation resulting in a greater offset between the axis of the roller and the axis of its associated axle provides a larger unbalanced load and thus a greater amplitude of vibration for the vibratory platform and vice versa.
A better understanding of the present invention will be had upon reference to the following detailed description when read in conjunction with the accompanying drawing, wherein like reference characters refer to like parts throughout the several views, and in which:
With reference first to
The vibratory table includes a base 12 which is supported on a ground surface. A vibratory platform 14 is movably supported above the base 12 by any conventional means, such as pneumatic bladders 16.
A vibratory assembly 18 is mounted to a bottom of the support platform 14. The vibratory assembly 18 is rotatably driven by a motor 20. The motor 20 is illustrated in
With reference now to
As best shown in
As best shown in
The gears 32 and 36 are dimensioned so that the gears 32 and 36 are in mesh with each other after assembly (
Although the mechanical coupler arrangement is illustrated in the drawing as the two gears 32 and 36, it will be understood, of course, that other means may alternatively be utilized to ensure that the shafts 24 and 26 rotate in the opposite rotational direction from each other and in synchronism with each other. For example, an endless belt in a figure eight configuration disposed between the shafts 24 and 26 will also achieve such synchronism of rotation in the opposite direction of the shafts 24 and 26.
With reference now particularly to
As best shown in
Each end cap 56, furthermore, includes a rectangular opening 58. This rectangular opening 58 is disposed over a square portion 60 of the shafts 24 or 26 which are complementary in shape. Consequently, with the end caps 54 disposed over their respective shafts 24 and 26 and secured to their respective rollers 50 and 52, the rotational position of the rollers 50 and 52 is fixed relative to their associated shafts 24 and 26, respectively.
The rectangular opening 58 in each end cap 54 is illustrated in the drawing as rectangular in shape having two short sides and long sides while the end portions 60 of the shafts 24 and 26 are illustrated as being square in shape with a side length substantially the same as the short side of the rectangular opening 58. Consequently, with the portion 24 positioned through the opening 58 in its associated end cap 54, some radial movement of the roller 50 or 52 in a predefined radial direction parallel to the long sides of the opening 58 can occur.
Referring now to
An L-shaped bracket 72 is positioned against the square portion 60 of the shaft 24 or 26 and so that one side of the bracket 72 is slidably positioned along the end cap 54. One or more screws 74 then slidably extend through the openings in the tab 70, registering openings in the bracket 72 and threadably engage threaded holes 76 formed in the shaft 24 and 26. A compression spring is also disposed between the tab 70 and the bracket 72 as best shown in
The tab 70, bracket 72 and spring 78 thus serve two purposes. First, since one bracket 72 is positioned at each end of the roller 50 and 52, the rollers 50 and 52 are trapped against axial movement with respect to their associated shafts 24 and 26. Secondly, the bolts 74 form an alignment pin which prevents rotational movement of the end caps 54, and thus their attached rollers 50 and 52, relative to their associated shafts 24 and 26. Consequently, both the rotational position and axial position of each roller 50 and 52 is fixed relative to its associated shaft 24 and 26.
With reference now to
As best shown in
With reference now to
With reference now particularly to
The inflation of each bladder 80 thus radially shifts its associated roller 50 and 52 against the force of the compression springs 78 (
The bladder 80 thus forms a shift mechanism for shifting the rollers 50 and 52 relative to their respective shafts 24 and 26. Other means such as a mechanical shifter, may alternatively be used without deviation from the spirit or scope of the invention.
The movement of the rollers 50 and 52 to the position shown in
In practice, the opposite and synchronous rotation of the rollers 50 and 52 effectively cancel out vibration in the horizontal direction since each roller 50 and 52 presents an equal but opposite horizontal force on the roller supports 22 and thus on the vibratory platform 14. Conversely, the rotation of the rollers 50 and 52 when unbalanced as shown in
Although the rollers 50 and 52 are used as counterweights, it will be understood that any type of counterweight other than a roller may alternatively be used.
From the foregoing, it can be seen that the present invention provides a vibratory table for therapeutic use which creates vibratory movement only in a vertical direction and in an amplitude which may be easily varied by the user. Having described my invention, however, many modifications thereto will become apparent to those skilled in the art to which it pertains without deviation from the spirit of the invention as defined by the scope of the appended claims.
