Patent Description:
Locomotion is a basic facet of human life. Mobility can, however, be difficult, injurious, or impossible for some. There are a variety of reasons for why a person may experience partial or complete mobility limitations: orthopedic conditions, neurological disorders, motor deconditioning, accident, injury, disease, and disability, for example. Continuing to move - or even attempting to move - can cause discomfort or injury.

Others may be injured or overweight but require exercise to become healthier. Some rehabilitation facilities have elaborate systems to partially support the weight of such patients, so that they may exercise toward health. The patients wear harnesses that are tethered to trolleys which ride in tracks in the ceiling. Such systems are complex, require assistance from a physical therapist, and are very expensive and thus limited in availability to the patient. Some of these systems provide a lifting force by spring, which changes as the user moves and displaces the spring. Others have sophisticated sensing technology which monitors movement of the patient and then adjusts the lifting force so as to provide a constant unweighting of the patient.

In some cases, movement may be possible and, indeed, easy, but the individual nonetheless wishes to lower his risk of injury from such movement. Athletes, for instance, often have a need to train long hours with great intensity. They balance the benefits of high- volume training against the elevated risk of injury. A competitive athlete can, after all, suffer serious physical and mental setbacks from even a mild injury. There are a variety of assistive devices to reduce the likelihood of injury during exercise. For example, runners may use buoyancy devices and run in the water. Or they may run on treadmills while zipped into a pressurized bag that lifts them slightly off the treadmill deck, thereby reducing foot-strike impact.

Physical therapists often have other devices which suspend from above to support the user while he or she moves. For example, devices exist which can be placed over or above a treadmill, usually with harnesses, hooks, or special clothing that partially lifts the patient while walking or running on a treadmill. These devices apply an upward force on a patient to reduce his impact while moving.

Of course, all of these solutions lack freedom of movement. The user is confined to a pool, a treadmill, or a pre-defined path set in ceiling tracks. The person cannot use any of these to walk to the bathroom or around the neighborhood, for example.

Further, and more seriously, each alters the normal pattern of motion during walking and running. Harnesses that hang from the ceiling tracks generally support the user at a single location, usually above the head or near the center of the back. Occasionally they lift the user at opposed sides of the hips. In both arrangements, the harness restricts the normal movement of the upper body during locomotion. The user may experience upward lift on one side of his body that is the same as that on the other side of this body. In other words, the user's left and right sides are lifted equally and simultaneously. In normal walking and running, however, the forces along the left side of the body are different than and independent from those along the right side of the body. Such systems do not account for these differences, and may exercise different muscles than those used in normal running and walking, thereby leading to improper or prolonged rehabilitation, therapy, or training.

Moreover, these systems may exercise different muscles than those used in normal walking and running, thereby leading to improper or prolonged rehabilitation, therapy, or training. The use of these devices in rehabilitation, therapy, or training fails to mimic real- life movement and may lead to improper recovery. An improved solution is needed.

<CIT> discloses a walker mechanism for invalids to control the weight pressure allowed on the legs of the invalid. It includes a wheeled carriage to partially support the body of the invalid in a harness, each side of the harness being supported by a cable having a spring.

<CIT> discloses a mechanism to support the weight of a patient so as to prevent the patient's legs from carrying their entire weight. The mechanism includes a spring from one end of which a spring wire extends to a cam, a cam wire which extends from the cam to a rope wheel, a rope which extends from the rope wheel to a moment arm group, another rope which extends from the moment arm group to another rope wheel, and a load wire which extends from the rope wheel to support the weight of the patient.

In an embodiment, a bodyweight unloading locomotive device comprises the features of the claims. Each of the unloading assemblies thereby exerts an independent unloading force on the harness with respect to the frame, encouraging natural movement and allowing independent unloading of the left and right sides of the body during such natural movement.

The above provides the reader with a very brief summary of some embodiments described below. Simplifications and omissions are made, and the summary is not intended to limit or define in any way the disclosure. Rather, this brief summary merely introduces the reader to some aspects of some embodiments in preparation for the detailed description that follows.

Reference now is made to the drawings, in which the same reference characters are used throughout the different figures to designate the same elements. Briefly, the embodiments presented herein are preferred exemplary embodiments and are not intended to limit the scope, applicability, or configuration of all possible embodiments, but rather to provide an enabling description for all possible embodiments within the scope and spirit of the specification. Description of these preferred embodiments is generally made with the use of verbs such as "is" and "are" rather than "may," "could," "includes," "comprises," and the like, because the description is made with reference to the drawings presented. One having ordinary skill in the art will understand that changes may be made in the structure, arrangement, number, and function of elements and features without departing from the scope and spirit of the specification. Further, the description may omit certain information which is readily known to one having ordinary skill in the art to prevent crowding the description with detail which is not necessary for enablement. Indeed, the diction used herein is meant to be readable and informational rather than to delineate and limit the specification; therefore, the scope of the specification should not be limited by the following description and its language choices.

<FIG> and <FIG> are front perspective and right side elevation views of a body weight unloading locomotive device <NUM> (hereinafter, the "device <NUM>") for support during movement, regardless of different and independent movements on both sides of the body. The device <NUM> provides independent, bilateral support proximate the hips of a user, to assist the user in self-propelled, locomotive motion. The device <NUM> includes an assembled frame <NUM>, four wheels <NUM>, and unloading assemblies <NUM> and <NUM> carried on the frame <NUM>. The unloading assemblies <NUM> and <NUM> are hidden in <FIG> and <FIG> by panels <NUM> carried on the frame <NUM>, but are much more visible in <FIG>. The unloading assemblies <NUM> and <NUM> are coupled to a harness worn by a user, as depicted in <FIG>, and operate to lift or unload some portion of the user's body weight on the left and right sides of the user's body.

The device <NUM> generally has a top <NUM>, an opposed bottom <NUM>, a front <NUM>, and an opposed back <NUM>. The word "generally" is used here to indicate a general area of the device <NUM>, rather than a specific point, element, feature, or the like. Further, description herein may be made to relative directions or orientations with respect to these terms top, bottom, front, back, and the description may indicate the arrangement of multiple elements or features with respect to each other in the context of above, below, in front of, behind, or the like, relying on the reader's understanding of the top <NUM>, bottom <NUM>, front <NUM>, and back <NUM> for contextual reference.

The frame <NUM> includes identical left and right sides <NUM> and <NUM> rigidly coupled to each other with a top tube <NUM> and a bottom tube <NUM>. Because the left and right sides <NUM> and <NUM> of the frame <NUM> are identical, only one is described here, with the understanding that the description applies equally to the other. The same reference characters are used for the structural elements and features of both the left and right sides <NUM> and <NUM>, and the reader will understand that the context or diction of the relevant description will convey whether the description is of the left or right side <NUM> or <NUM>.

The right side <NUM> includes a main tube <NUM> extending generally diagonally from the bottom <NUM> and back <NUM> of the device <NUM> to the bottom tube <NUM> of the frame <NUM> proximate the front <NUM>, approximately midway between the top <NUM> and bottom <NUM> of the device <NUM>. The main tube <NUM> has a rectangular cross-section, is hollow, and has a thin, strong, durable, but lightweight sidewall constructed out of a material or combination of materials having those properties, such as steel, aluminum, titanium, or carbon fiber. Other suitable constructive materials and cross-sections are included within the scope of this description.

The main tube <NUM> is coupled to a vertical tube or housing <NUM> which rises from the main tube <NUM> near the back <NUM> of the device <NUM>. Though the housing <NUM> is cylindrical, it is also hollow like the main tube <NUM>. The housing <NUM> holds part of the unloading assembly, as described later.

A front tube <NUM> extends diagonally downward, opposite the main tube <NUM>. The front tube <NUM> has an upper section which is nearly, but not quite, level, a long middle section which is diagonal, and a lower section which is nearly vertical. The top back of the front tube <NUM> is coupled to the top of the housing <NUM>, and the middle of the front tube <NUM> is coupled to the front of the main tube <NUM>. The front tube <NUM>, like the main tube <NUM>, preferably but not necessarily has a rectangular cross-section, is hollow, and has a thin, strong, durable, but lightweight sidewall constructed out of a material or combination of materials having those properties, such as steel, aluminum, titanium, or carbon fiber.

The bottoms of the main tube <NUM> and the front tube <NUM> are generally vertical. The bottom of the front tube <NUM> is open so as to receive a post <NUM>. The wheels <NUM> are mounted on the post <NUM> for rolling movement and for swiveling movement so that the device <NUM> can be pointed and moved in a desired direction. A series of vertically spaced-apart holes <NUM> are formed in the post <NUM>, and an adjustment knob <NUM> is threaded through the bottom of the front tube <NUM> and into one of the many holes <NUM>. The knob <NUM> allows vertical adjustment of the post <NUM> to change the height of the device <NUM> at the front <NUM>; the knob <NUM> may be loosened or released from front tube <NUM>, the post <NUM> slid up or down, and the knob <NUM> then tightened or re-engaged with the front tube <NUM>.

The bottom of the main tube <NUM> has a series of vertically spaced-apart holes <NUM> formed therethrough; these holes <NUM> receive an axle <NUM> of each of the wheels <NUM> at the back <NUM> of the device <NUM>. The axle <NUM> can be moved into any of the holes <NUM> to adjust the height of the device <NUM> at the back <NUM>. The axle <NUM> is secured with a pin <NUM>, such as a cotter pin or other suitable engagement, placed through the axle <NUM> on the opposite side of the main tube <NUM> from the wheel <NUM>. The wheels <NUM> in the back <NUM> preferably, but not necessarily, are mounted for rolling movement but not for swiveling movement.

The left and right sides <NUM> and <NUM> of the frame <NUM> are coupled by the top tube <NUM> and the bottom tube <NUM>. The top tube <NUM> is a rigid tube bent into a U shape, with a straight front section and two side sections or legs oriented at roughly ninety degrees to the front section. These legs are screwed, bolted, welded, or otherwise securely engaged to the top sections of the front tubes <NUM> on both the left and right sides <NUM> and <NUM>. Similarly, the bottom tube <NUM> is a rigid tube bent into a U shape, with a straight front section and two side sections or legs oriented at roughly ninety degrees to the front section. These legs are screwed, bolted, welded, or otherwise securely engaged to top sections of the main tubes <NUM> on both the left and right sides <NUM> and <NUM>.

When the user uses the device <NUM>, the user stands, walks, or runs behind the top and bottom tubes <NUM> and <NUM> and between the left and right sides <NUM> and <NUM>, as shown in <FIG>. As such, the top tube <NUM>, together with the left and right sides <NUM> and <NUM> and the bottom tube <NUM>, defines a user-receiving area <NUM> accessible from the back <NUM> of the device <NUM>.

A handlebar <NUM> extends forwardly at the top <NUM> of the device <NUM>. A cylindrical sleeve <NUM> is mounted along the top section of the front tube <NUM>; the sleeve <NUM> is hollow, its back is secured against the top of the housing <NUM>, and its front is open. A series of horizontally spaced-apart holes <NUM> are formed through the outside of the sleeve <NUM>; an adjustment knob <NUM> is threaded through the holes <NUM> and allows horizontal adjustment of the handlebar <NUM> to change the reach of the user when using the device <NUM>. The knob <NUM> may be loosened or released from sleeve <NUM>, the handlebar <NUM> slid into or out of it, and the knob <NUM> then tightened or re-engaged with the sleeve <NUM>.

The handlebar <NUM> is curved in several different directions. The back of the handlebar <NUM> is straight so that it may fit in the sleeve <NUM>. The handlebar <NUM> has a length, as shown in <FIG>, so that it extends forwardly beyond the top section of the front tube <NUM>. The handlebar <NUM> then bends inwardly for a short section, and then bends upwardly for a short section. Other handlebar <NUM> configurations are suitable as well.

The handlebar <NUM> is hollow and has a thin, strong, durable, but lightweight sidewall constructed out of a material or combination of materials having those properties, such as steel, aluminum, titanium, or carbon fiber. When a user is disposed in the user-receiving area <NUM> and operating the device <NUM>, the user can easily reach out and hold the handlebar <NUM>, gripping any portion thereof as is comfortable to steady the device <NUM> and assist in movement and steering.

<FIG>and <FIG> show the right side <NUM> of the frame <NUM>. In <FIG>, the panel <NUM> is removed so that the unloading assembly <NUM> is visible; <FIG> is a section view taken along the line <NUM>-<NUM> of <FIG>, just barely inside the frame <NUM>, such that the panel <NUM> is not visible and the frame <NUM> is partially sectioned. The unloading assemblies <NUM> and <NUM> are carried on, and partially within, the frame <NUM>; the unloading assembly <NUM> is on the left side <NUM>, and the unloading assembly <NUM> is on the right side <NUM>. Again, as above with respect to the left and right sides <NUM> and <NUM>, because the unloading assemblies <NUM> and <NUM> shown here are identical, only the unloading assembly <NUM> on the right side <NUM> will be described here with the understanding that the description applies equally to the other. The same reference characters are applicable to the unloading assembly <NUM> on the left side <NUM>. However, it should be understood that the unloading assemblies <NUM> and <NUM> need not be identical, and this description should not be limited so. Indeed, in some embodiments, it may be desirable to actually have different unloading assemblies. For example, where a user suffers from an asymmetrical weakness, the device <NUM> may be outfitted with intentionally different unloading assemblies <NUM> and <NUM> having different bend, load, and other performance characteristics. For example, for a patient recovering from a stroke, it may be advantageous to provide more unloading force to a side of the patient's body which has been more severely affected by the stroke, while providing less unloading force to the other side. Nevertheless, for the purposes of the description as it relates to the drawings, these particular unloading assemblies <NUM> and <NUM> are identical.

The unloading assembly <NUM> includes a flat spring <NUM>, a stacked cam assembly <NUM> on the flat spring <NUM>, a cable or tether <NUM> routed through the stacked cam assembly <NUM> and a series of pulleys mounted on the frame <NUM>.

The flat spring <NUM> is a sprung arm: a lightweight, compact, resilient and elongate flat spring member having a first, fixed end <NUM> and a second, a free end <NUM>. The fixed end <NUM> is secured in a sleeve mounted on a block <NUM> having an angled surface <NUM>. An adjustment knob <NUM> passes through a hole in the fixed end and into a threaded bore <NUM> in the block <NUM>. The adjustment knob <NUM> is thus threadably engaged to the block <NUM> and can be tightened and loosened to change the spring force of the flat spring <NUM>. For less spring force, the adjustment knob <NUM> is loosened and backed out of the bore <NUM>, which allows the fixed end <NUM> to rise slightly away from the angled surface <NUM> of the block <NUM>. For more spring force, the adjustment knob <NUM> is tightened into the bore <NUM>, which holds the fixed end <NUM> closer to the angled surface <NUM> of the block <NUM>. The adjustment knob <NUM> is a means for adjusting the spring force of the flat spring <NUM>; in other embodiments, the adjustment knob <NUM> may be an electric, electromechanical or electromagnetic adjustment, or an adjustable bolt, or some other means for changing the spring force.

Indeed, the flat spring <NUM> operates as a spring. It is mounted in a horizontal configuration. In this horizontal configuration, the free end <NUM> is above and behind the fixed end <NUM>, and it moves between a first, "unloaded" position as shown in <FIG>, in which the free end <NUM> is in a high position above the fixed end <NUM>, and second, loaded position as shown in <FIG>, in which the free end <NUM> is in a low position closer to the main tube <NUM>. This movement is indicated by the arcuate double-arrowed line A in <FIG>. It moves toward the loaded position in response to a weight being placed on the harness on the right side <NUM>, such as by the user walking, and pulling the flat spring <NUM> down via the tether <NUM>. In response, the flat spring <NUM> exerts a biasing force in a direction opposite the pull of gravity and vertical translation of the body downward during locomotion; the flat spring <NUM> acts to pull the tether <NUM> back. Other horizontal configurations are possible and may be suitable, including configurations which are vertically or horizontally flipped with respect to the above-described configuration. Generally, however, the horizontal configuration is defined as one in which the spring (the spring arm <NUM>, in this case) extends horizontally.

In this way, the flat spring <NUM> is just a spring which exerts a biasing force in opposition to displacement: extension or compression of a spring. And, in this sense, other springs may be suitable, such as coil springs, pneumatic springs, torsion springs, etc. The flat spring <NUM> has a non-linear force-displacement curve, such that the force required to displace the flat spring <NUM> increases as the displacement increases; at larger displacements, a larger force is necessary to displace the free end <NUM> by the same amount. The flat spring <NUM> produces a biasing force against its curve, toward the front <NUM> of the device <NUM>. As such, when the user is moving forward, this forward bias assists in moving the device <NUM> forward as well.

The stacked cam assembly <NUM> is mounted for rotation on the free end <NUM>. The stacked cam assembly <NUM> includes outer and inner cams <NUM> and <NUM>, placed side-by-side on the free end <NUM>. Both cams <NUM> and <NUM> are mounted for rotation with respect to each other about the same axis of rotation, however, the cams <NUM> and <NUM> are fixed to each other to prevent relative rotation.

The outer cam <NUM> is larger, and the inner cam <NUM> is smaller. Both cams <NUM> and <NUM> are eccentrics with different profiles or shapes; their axes of rotation are offset from their respective geometric centers, such that as they rotate, their lever arms change and the ratio of their respective lever arms change. In this way, with the tether <NUM> wrapped around the outer cam <NUM> and the tether <NUM> wrapped around the inner cam <NUM>, in grooves formed therein, the flat spring <NUM> and cam assembly <NUM> together form a constant-force displacement system. In other words, beyond a pre-determined pre-loaded displacement, additional displacement does not significantly change the force required for continued displacement. This is described in greater detail below. Further, in other embodiments of the device <NUM>, different cam combinations are used, including assemblies with three or more cams, cams of different sizes than presented here, similarly-sized cams, etc..

Another tether, an inelastic anchor cable <NUM>, is tied between the inner cam <NUM> and a tie-down <NUM>. This anchor cable <NUM> is part of the unloading assembly <NUM>. The tie-down <NUM> is an anchor preventing the end of the anchor cable <NUM> attached thereto from moving; the other end of the anchor cable <NUM> is fixed to the inner cam <NUM>. Mounted on top of the main tube <NUM> is a pulley assembly including three pulleys <NUM>, <NUM>, and <NUM>. One end of the anchor cable <NUM> is fixed to the top of the front of the inner cam <NUM> and lays in a groove therein before extending down to the pulley <NUM>. With rotation of the inner cam <NUM>, the anchor cable <NUM> wraps around the circumference of the inner cam <NUM> and effectively shortens the anchor cable <NUM>, bending the flat spring <NUM> toward the loaded position. The length of the anchor cable <NUM> can be adjusted at the tie-down <NUM> to increase or decrease the pre-load on the flat spring <NUM>.

The tether <NUM> has an opposite orientation on the larger outer cam <NUM>. It has two ends. One end of the tether <NUM> is fixed to front side of the cam <NUM>; this end is wrapped over the top of the cam <NUM> but in a different direction from the anchor cable <NUM>, such that it is fixed to the front side of the cam <NUM> and then extends over and around the circumference of the cam <NUM>. From there, the tether <NUM> extends downward to the pulleys <NUM> and <NUM>. The pulley <NUM> is partially mounted inside the housing <NUM>. As the tether <NUM> routes under the pulley <NUM>, it is redirected from a roughly vertical direction to a roughly horizontal one, and as the tether <NUM> routes under the pulley <NUM>, it is redirected from that roughly horizontal direction to a roughly vertical one inside the hollow housing <NUM>.

The three pulleys <NUM>, <NUM>, and <NUM> have parallel axes; each spins in the same direction. All three pulleys <NUM>, <NUM>, and <NUM> are mounted proximate each other, along the main tube <NUM>, and in the same plane, such that they only act to redirect the anchor cable <NUM> or tether <NUM> in a new direction along that plane. However, the tether <NUM> rises up from the pulley <NUM> inside the housing <NUM> to a different set of pulleys which orient the tether <NUM> for attachment to the harness.

<FIG> illustrate a pulley cassette <NUM> containing these other pulleys <NUM>, <NUM>, and <NUM> which redirect the tether <NUM>. The pulley cassette <NUM> is part of the unloading assembly <NUM> (or <NUM>) and is mounted for swinging movement in the housing <NUM> of the frame <NUM> and includes an outer housing <NUM> with an inner side <NUM> and an opposed outer side <NUM>. The outer side <NUM> is directed away from the frame <NUM>, inward into the user receiving area <NUM>. The inner side <NUM> is partially carried within the housing <NUM>. Proximate the top <NUM>, the housing <NUM> has a large open window <NUM>. The pulley cassette <NUM> swings forward and backward in this window <NUM>. Two discs <NUM> and <NUM> are secured within the housing <NUM>; the disc <NUM> is proximate the top <NUM>, and the disc <NUM> is just slightly lower. Extending coaxially between the discs <NUM> and <NUM> is a pin <NUM>. Fixed to the inner side <NUM> of the pulley cassette <NUM> is a leaf with a knuckle <NUM>. The knuckle <NUM> has a vertical bore which is loosely mounted over the pin <NUM>. Thus, the knuckle <NUM> pivots on the pin <NUM>, and the pulley cassette <NUM> swings with the knuckle between a forward position (shown in broken line in <FIG>) and a rearward position (shown in solid line) along the double-arrowed arcuate line B in <FIG> shows a wide range of angular movement, but preferably the pulley cassette is limited in swinging more than thirty degrees in front of or behind a neutral position, which is shown in <FIG>.

Within the housing <NUM> are three axles on which the pulleys <NUM>, <NUM>, and <NUM> are mounted for rolling movement. When the pulley cassette <NUM> is in the neutral position of <FIG>, these pulleys <NUM>, <NUM>, and <NUM> are mounted in a perpendicular offset fashion to the pulleys <NUM>, <NUM>, and <NUM>. The tether <NUM> extends up from the pulley <NUM>, inside the housing <NUM>, and routes over the first pulley <NUM>, then under the second pulley <NUM>, and then again over the third pulley <NUM>. A hole <NUM> is formed through the outer side <NUM> of the housing <NUM>, and a strong bracket mounted outside the hole <NUM> has a hole corresponding thereto. A stop <NUM> is secured on the tether <NUM> to prevent the tether <NUM> from being pulled into the pulley cassette <NUM> farther than desired.

In operation, a user uses the device <NUM> to assist in locomotive movement. The device <NUM> is useful for physical therapy, rehabilitation, and athletic training. Returning to <FIG>, a user <NUM> is illustrated in the user-receiving area <NUM> using the device <NUM>. The user is wearing a harness <NUM>. Any suitable harness <NUM> may be used; this harness <NUM> includes an adjustable waist belt <NUM>, adjustable thigh straps <NUM>, adjustable above-the-knee straps <NUM>, and outer or lateral straps <NUM> on each side of the harness <NUM> inelastically connecting the waist belt <NUM>, thigh strap <NUM>, and above-the-knee strap <NUM>. In <FIG>, the tethers <NUM> from both unloading assemblies <NUM> and <NUM> are shown directly attached to the waist belt <NUM>. Attachment of the tethers <NUM> to a point at the level of the region between the hip joint and the waist is preferred. In other embodiments, the tethers <NUM> may terminate with clips such as carabiners for coupling to loops on the waist belt <NUM>. The tethers <NUM> are attached to opposing sides of the waist belt <NUM>, just above the hip joints. In this way, each tether <NUM> independently acts on one respective side of the body.

The harness <NUM> couples the user <NUM> to the device <NUM>. When the user <NUM> walks, his hips move up and down. In normal locomotion, when the left leg is moved forward, his left hip rises slightly and his right hip drops slightly, and his pelvis rotates to a small degree. When it does, on the left side <NUM>, the cassette pulley <NUM> swings forward slightly, the tether <NUM> retracts (until limited by the stop <NUM> encountering the bracket <NUM>), and the flat spring <NUM> bends to a lesser degree toward its unloaded position. The force exerted by the flat spring <NUM> is in the forward direction, which assists in moving the device <NUM> forward slightly. At the same time, on the right side <NUM>, the cassette pulley <NUM> swings backward slightly, and the tether <NUM> extends to accommodate the dropping of the right hip and rotation of the pelvis. This pulls the tether <NUM> through the pulley cassette <NUM> and through the pulleys <NUM>, <NUM>, and <NUM>, thereby causing the cam assembly <NUM> to rotate and the flat spring <NUM> to bend to a greater degree. The left and right side <NUM> and <NUM> flat springs <NUM> independently exert a bias on the tethers <NUM> on their respective sides; in response, the user <NUM> feels his weight on both the right and left sides of this body at least partially unloaded. Further, because the unloading assemblies <NUM> and <NUM> each independently are a constant-force displacement system, rather than a simple spring force or exponential force displacement system, the user <NUM> experiences a constant or consistent unloading despite the extent of the displacement on either side. In other words, whether the user <NUM> raises his right hip or drops his right hip a little or a lot, the unloading force he experiences is constant. In yet other words, if the user drops his right hip a significant distance, he does not experience a proportionally greater unloading. For example, the device <NUM> can be set up to provide a constant <NUM> (fifty pounds) of unloading force. If the user drops his hip a little, he will feel that <NUM> (fifty pounds) of unloading; if the user drops his hip a lot, he will still feel that same <NUM> (fifty pounds) of unloading.

Moreover, the sides of his body move independently - and are allowed to move independently - because the unloading assemblies <NUM> and <NUM> are independent of each other. In more detailed operation, when the hip of the user <NUM> moves a distance, the tether <NUM> moves this distance as well, and unwinds from the cam <NUM>. The anchor cable <NUM> spools onto the cam <NUM>, shortening its effective length and causing the flat spring <NUM> to flex. The cam assembly <NUM> unreels and the flat spring <NUM> bends to a greater degree. Because the flat spring <NUM> and cam assembly <NUM> combine to form a constant-force displacement, however, the patient feels a constant upward unloading force on that side of the harness <NUM>. The displacement of the tether <NUM> - whether it is <NUM> or <NUM> (one inch or six inches) - does not cause a proportional change in the upward force. Rather, the displacement causes essentially no change in unloading force. In this way, the device <NUM> provides a constant unloading of each side of the user's body, independently of each other.

In other embodiments, a sensor <NUM> proximate one of the wheels <NUM> measures rolled distance. A sensor <NUM> in the stop <NUM>, or in the pulley cassette <NUM>, or somewhere along the tether <NUM>, measures acceleration and thus force, and possibly also angle of incline. The sensors <NUM> and <NUM> each may include a microprocessor, gyroscope, accelerometer, memory chip, PCB, and like electronic components. The readings from these two sensors <NUM> and <NUM> are correlated for later analytics; doctors and physical therapists can use this information to determine stride length, stance and swing phase duration, speed, work energy, and other kinematic and kinetic parameters of locomotion, and this information can be compared for each side of the body as well as over time to evaluate rehabilitation. Moreover, in some embodiments, these sensors <NUM> and <NUM> are coupled in wired or wireless data communication to a display head unit, such as a smartphone or other electronic device, preferably mounted on the top tube <NUM>, which displays such information to the user <NUM>. The user <NUM> can toggle through this and other information by depressing a physical button or touching the display of the head unit.

In some instances, the wheels of the device <NUM> may be removed. This removes the mobility of the device <NUM>, but it can instead now be placed on or around a treadmill. The bottom <NUM> of the frame may be bolted onto or otherwise secured to the treadmill using the holes <NUM> and <NUM>. Alternatively, pads or cushions applied to the bottom <NUM> of the frame <NUM> can support the device <NUM> around the treadmill. The user can then walk or run on the treadmill with his weight supported as described above.

<FIG> shows an alternate embodiment of the unloading assembly <NUM> of the device <NUM>. The below description applies equally to an alternate embodiment of the unloading assembly <NUM>. In this embodiment, two flat springs are used in combination. <FIG> is stylized in the form of a free body diagram, but a reader understanding the description hereto will nonetheless readily appreciate and understand <FIG>.

The flat spring <NUM> is mounted as in <FIG>: the fixed end <NUM> is fixed to the main tube <NUM> and the free end <NUM> is free. The cam assembly <NUM> is mounted for rotation to the free end <NUM>, and the anchor cable <NUM> is fixed while the tether <NUM> routes around the pulley <NUM> to extend to the harness. However, in this embodiment, a second flat spring <NUM> is used. The flat spring <NUM> is also a sprung arm preferably, but not necessarily, identical in structure, features, and construction to the flat spring <NUM>; it also includes a fixed end <NUM> and a free end <NUM>. The flat spring <NUM> is mounted in a parallel fashion to the flat spring <NUM>. As the term is used here, "parallel" is analogous to two elements in an electrical circuit and does not necessarily refer to a geometric relationship or alignment between the two flat springs <NUM> and <NUM>. Specifically, the flat spring <NUM> and cam assembly <NUM> are in a first position, and the second flat spring <NUM> is carried in a second position; the first and second positions are different but are registered with each other in a vertically offset fashion. The flat springs <NUM> and <NUM> in this embodiment are coextensive, but they need not be.

The second flat spring <NUM> is stacked above the flat spring <NUM>. A rigid, inelastic cable <NUM> ties or couples the free end <NUM> of the flat spring <NUM> to the free end <NUM> of the flat spring <NUM>, such that movement of the free end <NUM> immediately and directly imparts movement to the free end <NUM>. This coupled arrangement increases the spring force of the flat spring <NUM>. The tether <NUM> remains wrapped around the cam assembly <NUM> on the flat spring <NUM>. Stacking flat springs on the frame <NUM> in this way allows the device <NUM> to unload more weight from the user during operation. In other embodiments, three or more flat springs could be stacked, though this would not likely be necessary for all but the most demanding of weight needs.

<FIG> shows another alternate embodiment of the device <NUM>. While the unloading assembly <NUM> in <FIG> is mounted in a horizontal configuration in which the flat spring <NUM> extends rearwardly in a general direction and its free end <NUM> is behind its fixed end <NUM>, here in <FIG>, the unloading assembly <NUM> is mounted in a vertical configuration. This unloading assembly <NUM> is mounted on the vertical housing <NUM> rather than the horizontal top of the main tube <NUM>. The flat spring <NUM> is still mounted to the block <NUM>, but the block <NUM> is fixed vertically on the housing <NUM>, such that the flat spring <NUM> extends upward, rather than rearward. The free end <NUM> of the flat spring <NUM> is above the fixed end <NUM>, and when the flat spring <NUM> flexes, the free end <NUM> is displaced rearwardly toward the housing <NUM>. The flat spring <NUM> produces a biasing force against its curve, toward the front <NUM> of the device <NUM>. As such, when the user is moving forward, this forward bias assists in moving the device <NUM> forward as well. <FIG> shows in solid line the unloading assembly <NUM> in an unloaded position, and the unloading assembly <NUM> moves along the double-arrowed arcuate line C toward the housing to a loaded position, similar in displacement to the loaded position shown for the horizonal configuration of <FIG>. Other vertical configurations are possible and may be suitable, including configurations which are vertically or horizontally flipped with respect to the abovedescribed configuration. Generally, however, the vertical configuration is defined as one in which the spring (the spring arm <NUM>, in this case) extends vertically. The pulleys <NUM>, <NUM>, and <NUM> are also moved to a vertical arrangement, but the anchor cable <NUM> still routes through the pulley <NUM> and is secured to the tie-down <NUM>, which is on the housing <NUM>. The tether <NUM> also still routes through the pulleys <NUM> and <NUM> but now also extends through an additional pulley <NUM> which redirects the tether <NUM> upwardly through the housing to the pulley cassette <NUM>.

<FIG> shows yet another alternate embodiment of the unloading assembly <NUM> of the device <NUM>, somewhat similar to that shown in <FIG>. The below description applies equally to an alternate embodiment of the unloading assembly <NUM>. In this embodiment, two flat springs are used in combination. <FIG> is stylized in the form of a free body diagram, but a reader understanding the description hereto will readily appreciate and understand <FIG>.

The flat spring <NUM> is mounted as in <FIG>: the fixed end <NUM> is fixed to the main tube <NUM> and the free end <NUM> is free. The cam assembly <NUM> is mounted for rotation to the free end <NUM>, and the anchor cable <NUM> is fixed while the tether <NUM> routes around the pulley <NUM> to extend to the harness. However, in this embodiment, a second flat spring <NUM> is used. The flat spring <NUM> is also a sprung arm and is preferably, but not necessarily, identical in structure, features, and construction to the flat spring <NUM>; it also includes a fixed end <NUM> and a free end <NUM>. The flat spring <NUM> is mounted in a parallel fashion to the flat spring <NUM>, however, it is mounted below the main tube <NUM>, or opposite the flat spring <NUM>. As the term is used here, "parallel" is analogous to two elements in an electrical circuit and does not refer to a geometric relationship or alignment between the two flat springs <NUM> and <NUM>. Specifically, the flat spring <NUM> and cam assembly <NUM> are in a first position, and the second flat spring <NUM> is carried in a second position; the first and second positions are different but are registered with each other in a vertically offset fashion. The flat springs <NUM> and <NUM> in this embodiment are coextensive, but they need not be.

The second flat spring <NUM> is stacked below the flat spring <NUM> and has an inverted position: while the flat spring <NUM> flexes downwardly under a load, the second flat spring <NUM> flexes upwardly. An inelastic cable <NUM> couples the free end <NUM> of the flat spring <NUM> to the inner cam <NUM> at the free end <NUM> of the flat spring <NUM>, such that rotation of the inner cam <NUM> directly imparts upward movement of the free end <NUM> of the flat spring <NUM> as well as downward movement of the free end <NUM> of the flat spring <NUM>. The cable <NUM> passes through a bore <NUM> in the main tube <NUM>. This coupled arrangement increases the spring force of the unloading assembly beyond that of the unloading assembly <NUM> or <NUM>. The tether <NUM> remains wrapped around the outer cam <NUM> of the cam assembly <NUM> on the flat spring <NUM>. Coupling flat springs on the frame <NUM> in this way allows the device <NUM> to unload more weight from the user during operation. In other embodiments, three or more flat springs could be stacked on either side of the main tube <NUM> and coupled together, though this would not likely be necessary in all but the most demanding of weight needs.

In some embodiments, the cam assembly <NUM> need not be mounted directly onto the flat spring <NUM>, or, in other words, the cam assembly <NUM> can be separate from the spring. For example, the flat spring <NUM> of <FIG> could be modified to be a rigid, inflexible, unyielding arm <NUM>. In this embodiment, the cam assembly <NUM> is simply mounted to an arm <NUM>, similar to a rigid post, above the main tube <NUM>. The arm <NUM> is thus simply considered part of the frame <NUM>, or a rigid extension thereof. The cam assembly <NUM> is thus coupled to the second or free end <NUM> of the bendable flat spring <NUM> with the inelastic cable <NUM>, and to the harness with the tether <NUM>. The flat spring <NUM> is the only arm that moves in this arrangement; when the harness drops, the tether <NUM> pulls on and rotates the cam assembly <NUM>, and the cable between the cam assembly <NUM> and the flat spring <NUM> pulls on and bends the flat spring <NUM>. This embodiment is exemplary of unloading assemblies in which the cam assembly and the flat spring are separate, illustrating that the cam assembly need not be carried on or mounted to the flat spring. Indeed, the unloading assembly still operates effectively as a constant-force displacement system when the cable <NUM> (or anchor cable <NUM>) couples the cam assembly in one direction to a spring (such as the flat spring <NUM>) and the tether <NUM> couples the cam assembly in an opposing direction to the harness, regardless of the mounting of the cam assembly on or off the spring. This alternate version of <FIG> describes such an arrangement in an exemplary fashion. In other embodiments, the spring arm and cam assembly may be separated and not mounted to each other, and the arrangement of the cam assembly and spring arm are actually reversed: the cam assembly <NUM> is mounted on the main tube <NUM>, the spring arm <NUM> is mounted on the main tube <NUM> apart from the cam assembly <NUM> extends away, an anchor cable <NUM> coupled to a tiedown <NUM> extends to the cam assembly <NUM>, and then a tether <NUM> extends from the cam assembly <NUM> to over the free end <NUM> of the flat spring <NUM> and then toward the harness (likely through a pulley assembly).

Claim 1:
A bodyweight unloading locomotive device comprising:
a frame (<NUM>) for supporting locomotive movement, the frame having opposed left and right sides (<NUM>, <NUM>);
a harness for supporting a user between the left and right sides (<NUM>, <NUM>);
an unloading assembly carried on each of the left and right sides, wherein each unloading assembly comprises:
a spring (<NUM>) having a first end (<NUM>) fixed to the respective left and right side, and an opposed second end (<NUM>);
a cam assembly (<NUM>) having an outer cam (<NUM>) and an inner cam (<NUM>);
a tether (<NUM>) routed through the outer cam (<NUM>) of the cam assembly and extending to the harness; and a cable (<NUM>) routed through the inner cam (<NUM>) of the cam assembly and extending to one of an anchor (<NUM>) on the frame and the second end of the spring;
wherein each of the unloading assemblies exerts an independent unloading force on the harness with respect to the frame.