Adjustable motion wheel chair

An adjustable motion wheel chair having a mobility base for supporting a back panel and a seat panel. A pair of control plates are mounted to the mobility base and positioned laterally across the mobility base in spaced apart parallel relation. The back panel includes a pair of pivot pins located on opposite lateral edges of the back panel which are pivotally received by a respective control plate. A linkage member hingedly connects the seat panel to the back panel. Each control plate includes a forwardly extending stop for limiting the downward movement of a front edge of the seat panel. A latch member is attached to each control plate and is operable between a first position where the back panel is fixed in angular relation with the seat panel and a second position where the back panel is rotatable with respect to the seat panel.

BACKGROUND OF THE INVENTION

The present invention relates to an adjustable motion wheel chair which can be used in either a static mode with a back panel and seat panel in a fixed relation and can also be used in a dynamic mode where a user can stretch out to an extended position rather than a seated position while using the chair.

Wheel chairs are well known and wheel chairs allowing a user to stretch out to an extended position are also known. For example see U.S. Pat. No. 6,488,332 B1 to Markwald.

SUMMARY OF INVENTION

The present invention relates to an adjustable motion wheelchair which is completely adjustable to accommodate a user's size and degree of disability; to enable active movement; and to provide comfort. The wheel chair may be adjusted in a static position to allow for a selected angle between the back panel and the seat panel, pivotal at a point near the anatomic hip pivot. The wheel chair can be further adjusted to allow the seat and back of the wheel chair to be pivoted to a selected degree of tilt with the back panel and seat panel remaining in a constant angular position, around a point close to the center of gravity. Further, the wheel chair has a latch mechanism which when released allows the wheel chair to be used in a dynamic mode which allows the user to stretch out to an extended position and be able to return to the seated position. This allows a user of the wheel chair to extend and reinforce symmetrical movement patterns while in the wheel chair.

DESCRIPTION OF A PREFERRED EMBODIMENT

An adjustable motion wheel chair10according to the present invention is shown inFIG. 1. The wheel chair10according to the present invention is constructed of two main components, namely, a base frame portion, referred to in the industry as a mobility base,12as shown inFIGS. 1 and 2and a removable chair assembly14as shown inFIGS. 1 and 3. The mobility base12includes a pair of side frame members16supporting a pair of hand driven wheels18and also a pair of front idler wheels20. At the rear of the mobility base12a pair of anti-tip stops (only one is shown) are used to prevent the mobility base12from tipping in the rearward direction. Cross bracing members24are provided to separate the two side frame members16.

A pair of spaced apart and parallel arranged control plates26are pivotally mounted with pins28to a respective side frame16as shown inFIG. 2. Two cross bracing members30extend between the control plates26and are secured thereto as shown inFIG. 2. A pair of tubular sleeves32extend between and through the cross members30as shown inFIG. 2. The control plates26include a sector shaped portion having a series of spaced apart index holes38. The peripheral edge is provided with a series of notches40.

A rod34is slidably received by each of the tubular sleeves32and includes a limiting member36located at a distal end thereof. The rods34may be extended to a desired position and locked in place.

A pair of catch members42are slidably mounted on the side frame members16as shown inFIGS. 2 and 4. Each catch member42includes a pair of parallel spaced apart plates44which have been spaced apart a distance to slide into notches40as shown inFIG. 5. The pair of catch members42are mounted to opposite distal ends of a pull rod46. The pull rod46is spring biased toward the notches40but can be pulled outwardly causing the catch members42to slide away from the notches40to disengage the catch members42from the notches40. After disengaging the catch members42from the notches40the control plate26can be rotated about pins28. The rod46can then be released to enable the catch release42to engage selected notches40of the control plates26.

Each control plate26is provided with a slot200as shown inFIGS. 2 and 4. A retractable rod202extends across the slot200as shown inFIG. 4. Each rod202is connected with a pull cable204to a twist handle206mounted on a cross bracing member207. The cable204is threaded through a protective sheath208and a position guide. By twisting the handle206, the pin202is retracted from the slot200.

The chair assembly14is shown inFIG. 3. The chair assembly14includes a back frame48for supporting a back panel50. The back panel50is secured to back frame48with a frictional lock56. By loosening frictional lock56the panel50can be moved up or down on back frame48. By tightening lock56the panel50is secured at a selected position.

A seat panel62of chair assembly14is supported by a seat frame58as shown inFIG. 3.

A push handle68is mounted to the frame48with hinge members70as shown inFIG. 7. The hinge member70allows a user to tilt the handle68with respect to the frame48by a selected amount and then allow the user to lock the handle at the selected position.

A pair of linkage members74are attached to the back frame48in an orthogonal relation as shown inFIG. 3. Similarly, a pair of seat linkage members76are attached in orthogonal relation with the seat frame members58also as shown inFIG. 9. Each of the linkage members74are pivotally joined to a respective seat linkage member76with a pin78. An outwardly protruding pin79is secured to a respective linkage member74on opposite sides of the chair assembly14. The pins79are sized to be received by the slot200provided in the control plate26shown inFIGS. 4 and 5.

A pair of extenders80are connected between the seat frame58and an adjustable elbow hinge82as shown inFIG. 3. The elbow hinge82is also connected to tubular leg extension members84. In a preferred embodiment the elbow hinge82has a conventional mechanism to allow a user to lock extenders80and leg extension members84at a selected angular position.

A telescoping tube88is received by tubular leg extension member84. The relative position between tubular leg extension84and the telescoping tube88is set by pins90which extend through leg extension member84and the telescoping tube88as shown inFIG. 3.

A foot rest92is pivotally connected to the telescoping tubes88with a pin94.

A tubular member102is mounted between the back linkage members74as shown inFIGS. 6 and 7. A pair of pins104are held within the tube102and protrude outwardly under bias of a spring (not shown) within the tube102. A cable pull106is used to retract the pins104against the bias of the spring when cable106is pulled. Once the cable pull106is released, the pins104are allowed to extend outwardly from tube102. The pins104are sized to be slidably received by the holes38provided in the control plates26as shown inFIGS. 2 and 4.

In using the present invention, the chair assembly14is placed over the mobility base12with pins79located within the slots200provided in the control plates26of the mobility base12. The twist handle206is used to retract the rods202from slots200to allow the pins79to nest in the slots200. The twist handle206is then released whereby the rods202lock the pins79within the slots200as shown inFIG. 1 and 1a.

The cable pull106is then pulled to retract the pins104within the tube102and the back panel50is rotated about pins78and79until a selected angular relationship between the back panel50and seat panel62, known as the hip angle, is achieved. Once the angular position has been selected, the cable pull106is released causing the pins104, under spring bias, to extend into a corresponding hole38provided in the control plate26. Once the pins104, are positioned in the selected holes38, the angular position between the back panels and the seat panels is set for operation in the static mode.

Next the rod46may be pulled outwardly and the control plates26rotated on pins28thereby allowing the back panel and seat panel combination to be tilted to a selected position. The rod46is then released and the catch42engages a selected notch40at the desired tilt position.

The elbow hinges82can be adjusted to allow either free movement of the leg extension member84or the elbow hinges82can be locked to maintain a selected angular relation of the leg extension members84to the seat panels.

When the pins202are positioned to hold pins79in the notches40, the wheel chair is latched in a static mode where the back panel and seat panel are locked in the set angular relation as shown inFIGS. 1 and 1a.

When the wheel chair assembly10is to be used in a dynamic mode the twist handle206is twisted to retract pins202and to allow the pins79to rise out of the notches40. When this occurs the angular relation between the back panel and the seat panels of the wheel chair assembly14can be increased or decreased simply by the user leaning back on the back panel. The back panel pivots on the pins104positioned in the holes38of the control plates26and the seat panel pivots about the pins78connecting linkage members74and76. The pins79freely rise in the slots200allowing a user to stretch out to an extended position. The front edge of the seat frame members58rest on the limiting members36provided in the mobility base12and the weight of the seat panel is supported by the engagement with the limiting members36and the pins78. When the rods34holding the limiting members36are extended the pressure required to tilt the seat panel is increased and when the rods34are retracted the pressure required to tilt the seat panels is decreased. The chair10configured for use in the active mode is shown inFIGS. 8 and 8a.

The therapeutic wheel chair10according to the present invention provides a versatile wheel chair which can either be used in a static mode as a conventional wheel chair or can be used in a dynamic mode to allow a user to extend and reinforce symmetrical movement patterns using the wheel chair assembly as a support.

When the chair is not to be used, the cable pull106is used to disengage the pins104from the holes38of the control plate26and the back frame48may be rotated forwardly about the pins78, connecting the linkage members74and78, to a position where the back panels rest over the seat panels. In this way the unit may be collapsed to a space saving configuration.

It is understood that although the described embodiment relates to a wheel chair that other chairs could be used equally well.

While the fundamental novel features of the invention have been shown and described, it should be understood that various substitutions, modifications and variations may be made by those skilled in the art without departing from the spirit or scope of the invention. Accordingly, all such modifications or variations are included in the scope of the invention as defined by the following claims.