Abstract:
A wheel chair drive apparatus includes a frame having a wheel mount, a battery mount, and a control shaft mount. A drive wheel has a drive motor incorporated within the drive wheel. A battery is in operative communication with the drive motor via a detachable jack. A battery housing is dimensioned to mount in the battery mount of the frame and has a handle. A control shaft pivotably mounted on the control shaft mount, so that it has a stow position, and operating position, a user entry position and a table use position. A caster lever is pivotably mounted to the frame, so that it has a rolling position and an engaged position. The caster lever is disposed to engage a receiving seat on a wheel chair. A locking lever is releasably biased toward a position locking the caster lever in the engaged position.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     None.  
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT  
       [0002]     Not Applicable.  
       APPENDIX  
       [0003]     Not Applicable.  
       BACKGROUND OF THE INVENTION  
       [0004]     1. Field of the Invention  
         [0005]     The present invention is in the field of motorized wheel chairs, particularly, separable apparatuses attachable to standard wheel chairs to provide power to drive them.  
         [0006]     2. Related Art  
         [0007]     Substantial obstacles to mobility and everyday tasks of living continue for those disabled and bound to wheel chairs. There is a continuing need to make mobility for the wheel chair bound more reliable and convenient.  
         [0008]     Motor drives for standard wheel chairs exist in the prior art. U.S. Pat. No. 5,494,126 to Meeker and U.S. Pat. No. 5,050,695 to Kleinwolterink Jr. describe motor drive units that may be attached to standard push wheel chairs.  
         [0009]     U.S. Pat. No. 5,050,695 describes a geared brush type DC motor chain coupled to a very small drive wheel. It makes use of a fixed steering column. Only the height of the column can be adjusted to fit individual needs, by loosening a setscrew. The drive wheel is coupled to a frame though a bearing journal. The frame forms a well into which two large batteries are supported. Power is applied to the motor through a cable and is controlled with the control box at the top of the steering column. The speed and direction of the motor is accomplished through wings attached to the control box. The wings are attached to simple switches inside the control box. The patent further describes pivotal frames attached to the rear section of the wheel chair frame. Attached to the pivotal frames are sockets into which an inverted U-shaped crossbar is inserted. When the unit is connected to the wheel chair, two hooks on the rear of the frame hook onto the U-shaped crossbar, which lifts the rear of the frame. Two rails on each side of the frame come in contact with the X-frame of the wheel chair and this lifts the front of the wheel chair. This procedure locks the unit in place.  
         [0010]     U.S. Pat. No. 5,494,126 describes an apparatus and method for attaching a motorized wheel to a wheel chair. This unit is attached to the front of the wheel chair through the use of two brackets bolted to the front tubes of the wheel chair. The steering column is telescopically connected to the drive wheel and held in place with a collar and a setscrew. When connecting the drive unit to the wheel chair the steering column is replaced with a temporary installation handle. After the installation handle has been inserted it is held in place with a collar and set screw. The unit is then held in a partially upright position and two posts are guided into the C shaped openings of the brackets on either side of the front of the wheel chair. The occupant then presses forward on the installation handle forcing the drive wheel back under the front of the wheel chair. After the drive wheel is all the way under the front of the wheel chair the operator must then hold it in place and slide two pins into the brackets on either side of the wheel chair. These locking pins are then held in place with locking screws. The operator must then loosen the setscrews holding the installation handle in place, remove the installation handle and then install the battery. Next replace the steering column and lock the steering column in place with a collar and setscrew. Two, wires with spade lugs must then be connected to the battery with terminal screws. It is possible to connect the wires backwards.  
         [0011]     These devices are cumbersome in their operation, installation and transportation. The units are heavy and do not disassemble or collapse into a compact package. This creates difficulty in packing, as for example in the trunk of an automobile. Weight represents a substantial hardship, particularly for the elderly person, whose caregiver is commonly an elderly spouse. Prior art devices are also bulky and do not collapse into a small enough package for convenient transportation, again as in the trunk of a car.  
         [0012]     The prior art units do not have batteries that are easily removable. Moreover, the batteries are not encased in a separate housing. Accordingly, separate packaging of the batteries is required to transport prior art batteries on public transportation such as commercial airlines. There is no provision for re-charging the batteries.  
         [0013]     The prior art devices have in common a vertical shaft for holding a control module where the wheel chair occupant may reach it. This shaft is not movable, and accordingly obstructs ingress and egress from the wheel chair. The unadjustable vertical control shaft makes simple tasks difficult, such as pulling the chair up to the table, as for reading or a meal.  
         [0014]     These units are also difficult to install for a caregiver. They are prohibitively difficult for the disabled individual themselves to install. This is due to the mounting apparatus, which cannot automatically seat itself by simple engagement with the chair, which has no alignment guides to ease installment and which also prevents folding the chair up for storage when the apparatus is attached.  
         [0015]     The prior art devices have inefficient drive trains that use drive chains and further necessitate inefficient gearing and small drive wheels. Their systems are only 35% efficient. This inefficiency leads to a choice between either large, heavy batteries or smaller batteries that use an inordinate amount of power with an appreciably shorter charge life.  
         [0016]     In operation, the prior art units use small drive wheels that too readily transfer shock from minor impediments, such as a brick floor. Even slightly larger objects, such as a cobble stone street, become virtually impossible to traverse.  
         [0017]     It is in view of the above referenced shortcomings that the present invention was developed.  
       SUMMARY OF THE INVENTION  
       [0018]     The invention is an improved drive device for attachment to the standard wheel chair. The device is separable into two separate components for transportation. One component is a battery, contained in a separate, sealed housing. The battery and housing have a separate handle and are dimensioned to be of a convenient size and weight. The remaining second component includes a frame, high torque electric motor, drive wheel, and collapsible control shaft.  
         [0019]     This invention consists of a motorized wheel chair drive unit providing steerable motive power, which can be easily attached to or detached from a standard manual wheel chair and makes use of a direct drive system. This drive requires no gear reducers and no coupling mechanisms such as chains or belts. This drive system is much more efficient than those used in prior art. The efficiency is approximately 80% . This allows a choice between using a smaller battery which travels the same time and distance as prior art, and using a full-size battery which travels a much greater distance without recharging. It is preferred to use a smaller battery, which in this design is enclosed in a steel case.  
         [0020]     The drive motor is inside the drive wheel in one embodiment. In another, the wheel is the motor. It is an inverted rotor design with a stationary stator at the center of the motor and the rotor on the outside. The tire is molded directly on the outside of the rotor.  
         [0021]     The motor wheel has a relatively large diameter of eight and half inches. This permits easy passage over fairly large obstructions such as doorsills. The motor incorporates two large permanently lubricated sealed ball bearings. The wiring passes out through the center of one of the bearings, up under a protective cover to the electronic control box located above the motor The unit overcomes restrictions of prior art of approaching a desk, a table, a bathroom sink, a water fountain and a myriad of other places by allowing the steering column to be released and rotated back in the operator&#39;s lap. From the locked upright position, the steering column can also be folded forward down against the floor and then turned to the side, providing complete open access for entering and leaving the wheel chair. There is a release knob, located near the front edge of the wheel chair seat, which provides easy access for moving the steering column. When the release knob is pulled, the motor control is automatically turned off. In order to allow this feature to be effective the motor control head at the top of the steering column must be very slim and small. With the unit disconnected from the wheel chair and the battery pack removed, the steering column can then be folded down over the top of the frame where it locks in a centered position. This minimizes the space required for storing the unit and also provides a handle for moving the folded unit.  
         [0022]     The process of connecting and disconnecting the unit with the wheel chair is quick and easy, requiring no tools, allowing a handicapped person to fix the drive apparatus in place under the wheel chair for use.  
         [0023]     There are two lightweight brackets bolted to the inside rear of the wheel chair frame with outward slanted guides. There are engagement seats for the driver apparatus formed on the inner surface of these brackets. A swing assembly or caster lever is hinged at the rear of the drive apparatus&#39; frame. It rotates out approximately 45°. The swing assembly rotates over center and is held in the out position by the weight of the battery, and supported by two roller casters. The swing assembly supports a horizontal rectangular bar, which is transverse to the wheel chair and extends almost the full width of the inside of the wheel chair frame. The casters are mounted near the outer end of this horizontal bar. Mounted to the top of the battery handle is an inverted V delrin slide. To connect the unit, the swing assembly must be in the out position, and the steering column turned at 90° (to act as a brake). The wheel chair is moved over the drive unit, and as the horizontal bar comes in contact with the slanted guides on the wheel chair brackets the roller casters allow the unit to be guided laterally until the rectangular bar is captured by the engagement seats on the wheel chair brackets. As the wheel chair moves further forward, the swing assembly is driven to an upright vertical position. It is held in this vertical position by a releasable latch mechanism. As the swing assembly is driven to the upright vertical position, the rear of the frame is lifted which pushes the inverted V delrin slide against the bottom of the X-frame of the wheel chair. This lifts the front of the wheel chair and at the same time the roller casters are lifted off the ground. With the front of the wheel chair lifted, needed weight is added to the motor wheel providing better traction.  
         [0024]     A second means of connecting the unit can be accomplished by applying the brakes on the wheel chair. The drive apparatus can then be backed under the wheel chair using the power of the drive unit. This design results in a three-wheeled device with a very short wheelbase. Since the front casters of the wheel chair are only slightly lifted off the ground, they serve as outriggers and prevent the unit from tipping.  
         [0025]     Further features and advantages of the present invention, as well as the structure and operation of various embodiments of the present invention, are described in detail below with reference to the accompanying drawings.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0026]     The accompanying drawings, which are incorporated in and form a part of the specification, illustrate the embodiments of the present invention and together with the description, serve to explain the principles of the invention. In the drawings:  
         [0027]      FIG. 1  is a left side view of the drive apparatus for a wheel chair;  
         [0028]      FIG. 2  is a front view of the drive apparatus for a wheel chair  
         [0029]      FIG. 3  is a right side view of the drive apparatus for a wheel chair;  
         [0030]      FIG. 4  is a top view;  
         [0031]      FIG. 5  is a top view with the battery removed;  
         [0032]      FIG. 6  is a side view with a cutaway depiction of the engagement of the swing arm assembly with the wheel chair mounting brackets in a first position;  
         [0033]      FIG. 7  is a side view with a cutaway depiction of the engagement of the swing arm assembly with the wheel chair mounting brackets in a continuing position;  
         [0034]      FIG. 8  is a side view with a cutaway depiction of the engagement of the swing arm assembly with the wheel chair mounting brackets in a final position;  
         [0035]      FIG. 9  is a side view of the drive apparatus with the battery removed and the control shaft collapsed for storage;  
         [0036]      FIG. 10  is a top view of the drive apparatus with the battery removed and the control shaft collapsed for storage;  
         [0037]      FIG. 11  is a right side view of the drive apparatus with the battery removed and the control shaft collapsed for storage;  
         [0038]      FIG. 12  is a close up of the control module;  
         [0039]      FIG. 13  is a right sided view with the controls shaft in a user access position;  
         [0040]      FIG. 14  is a close up view of the battery housing; and  
         [0041]      FIG. 15  is a side view of the unit installed for operation in the standard wheel chair.  
         [0042]      FIG. 16  is a close up view of a mounting bracket;  
         [0043]      FIG. 17  is a top view of a wheel chair with a cut away; and  
         [0044]      FIG. 18  is a rear view of a wheel chair with a cut away.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0045]     Referring to the accompanying drawings in which like reference numbers indicate like elements,  FIGS. 1, 2 ,  3 ,  4  and  5  are side, front, side and top views, respectively, of the wheel chair motor drive of the present invention.  FIG. 15  shows the motor drive apparatus  10  engaged with a wheel chair.  
         [0046]     The wheel chair motor drive apparatus  10  is comprised of a frame  12  and, when assembled, a battery housing  14 .  
         [0047]     Drive wheel  20  comprises the housing for a high torque electric motor (not shown) within the wheel in the depicted embodiment. The wheel  20  is also the rotor of the electric motor, as well as the casing for the stator housed within it. The motor and wheel  20  are coaxial in the depicted embodiment. The wheel  20  also has a friction surface or tread  22  disposed circumferentially thereon.  
         [0048]     The drive wheel axle  24  supports drive wheel forks  26 . The forks  26  are fixedly attached to a fork bearing journal  28  which is substantially vertical in the depicted embodiment.  
         [0049]     The frame  12  is essentially comprised of a front frame component  30 , arm  32  and battery mount  34 .  
         [0050]     A control shaft  40  is fixedly attached to control shaft bracket  42 . The control shaft bracket  42  is attached at pivot  44  to the front frame component  30 .  
         [0051]     Control shaft bracket  42  straddles a control shaft positioning disk  38 . Control shaft  40  can pivot around pivot  44  through an arc that is forward and back, when drive wheel  20  is pointed frontwards. The position of the control shaft  40  may be selectively maintained at different positions along its arc of travel. In the depicted embodiment, bosses and detents (not shown) engaging between control shaft bracket  42  and an engaging edge of the control shaft position disk  38  are actuated by control shaft locking pin  46 , which spring biases a pin (not shown) in any of the series of detents (not shown) along a circumferential surface of control shaft positioning disk  38 . An alternative within the scope of the present invention is a friction engagement between a control shaft locking member and the control shaft position disk, allowing a continuous range of selectable positions from control shaft  40 . In any case, control shaft  40  may be positioned in a fully forward location,  40 A ( FIG. 13 ). This position, which in the depicted embodiment would place the top end of the control shaft  40  on or near the floor, allows for greatly simplified egress and ingress of the wheel chair occupant in and out of the wheel chair with the wheel chair drive unit  10  positioned under the wheel chair and either engaged with the wheel chair or ready for engagement with it.  
         [0052]     A fully retracted or backwards position of shaft  40 , position  40 C ( FIGS. 9, 10  and  11 ), is for stowing the wheel chair drive apparatus  10 . Position  40 C provides a compact dimension and smaller overall package size, which facilitates storing the wheel chair drive apparatus in the trunk of a car, or in provided storage on public transportation or elsewhere in a home or office.  
         [0053]     Control shaft  40  may also be positioned at table position  40 B (in phantom,  FIG. 3 ). The prior art mounted adjustable control shafts restricted the proximity the wheel chair occupant could achieve to a table or sink for activities of daily living such as eating a meal, reading or washing. Position  40 B allows a control shaft  40  to move backwards towards the wheel chair occupants lap and allow the wheel chair occupant to move forward with his or her knees under a table, desk or sink which in turn facilitates a comfortable distance for eating, reading, washing or other activities.  
         [0054]     On top of control shaft  40  are located controls, such as throttle  50 , displays ( FIG. 12 ) and handle bars  52 .  
         [0055]     Power for the wheel chair drive apparatus of the present invention is DC. The DC battery is retained within a battery housing  14 . This sealed housing is acceptable for public transportation such as commercial airlines, further easing travel for the disabled, who would otherwise need to make special arrangements for packaging an open battery for transportation.  
         [0056]     The battery housing  14  includes a handle  18  and a power jack receptacle  16 . The battery housing  14  is assembled with the wheel chair drive apparatus  10  by lowering it into the battery mount  34  of frame  12 . In the depicted embodiment, the battery mount is simply two parallel steel rails dimensioned to receive the battery housing  14  and support its weight flanges on the sides of the top of the battery housing  14 .  
         [0057]     A power cord  60  has a jack  62  that may be engaged with the corresponding jack  16  during assembly in order that the battery within housing  14  can be electronically engaged with the electric motor within drive wheel  20 . In the depicted embodiment, the power cord  60  progresses through front frame component  30  and down one arm of drive wheel fork  26  and enters the drive wheel casing  20  via a through hole in axle  24 .  
         [0058]     This battery pack is much lighter, approximately 30 lbs., and is internally fused with an enclosed protected connector. If needed, the system provides use of a second battery pack, which can be charging while the first is in use. The battery pack drops into the rectangular opening of the frame and is held in place by gravity. Four bolts located on either side of the battery pack, which holds the cover of the battery pack in place, prevents the battery pack from dropping through the rectangular opening in the frame. The connector is polarity keyed and rated at 50 amps with 10,000 insertions. To charge the battery, the connector providing power to the drive unit is removed from the battery and the battery charger connector is inserted into the battery pack. It is not necessary to remove the battery pack from the drive unit while charging. A connector of this quality requires high contact pressure and therefore an ejector mechanism  63  is preferred.  
         [0059]     At the rear of the wheel chair drive apparatus  10  is the swing assembly  70 . In the depicted embodiment, the swing assembly is a lever for casters  72 . Swing assembly  70  has at least two positions. A first position is substantially upright, at right angles with the battery mount rails  34  (see  FIGS. 8, 9 ,  10 ,  11  and  15 ). In this position, the swing assembly may be engaged with swing assembly brackets fixedly mounted to the wheel chair further explained below. In the first position, casters  72  are raised from and disengaged with the ground or floor. The first position is used for engagement with the wheel chair and use of the wheel chair drive assembly for powered driving of the wheel chair. The first position is also used for storage of the wheel chair drive assembly  10  when being transported or otherwise not in use (see,  FIGS. 9, 10  and  11 ). With regards to storage, the first position provides a more compact package size, and maintains the casters  72  in a position disengaged with the ground.  
         [0060]     Swing assembly  70  is engaged with the battery mounting rails  34  of frame  12  at pivot  74 . Movement of pivot  74  allows for a swing assembly  70  to move into at least one other position. This other position is depicted in  FIGS. 1, 3 ,  6  and  13 . An intermediate position is show in  FIG. 7 . There it can be seen that casters  72  are rotated into a position engaging them with the ground for rolling. Caster mounts  76  are angled such that the castors roll in the second position and do not touch the ground in the first position. The caster mounts  76  are fixedly attached to the swing assembly horizontal bar  78 . The swing assembly bar  78  engages with swing assembly mounting brackets, as is more fully described below. This second position of the swing arm assembly  70  is maintained in position and prevented from further backwards rotation by a stop engagement with the battery mounting rails  34  of frame  12 . Although any stop arrangement is within the scope of the present invention, in the depicted embodiment, the stop is the leading edge of the horizontal member of the swing assembly, which comes into stopping contact with the top of battery mounting rails  34  when the swing assembly  70  has been rotated to a position engaging the casters  72  with the ground.  
         [0061]     The swing assembly  70  includes a forward extension  80  having a locking notch  84 . When fully engaged with the wheel chair for driving it, the wheel chair drive apparatus  10  transfers forwards, backwards and turning drive force to the wheel chair through the close, fitted engagement of swing assembly horizontal bar  78  with the horizontal bar mounting brackets, which are fixedly attached to the wheel chair. Accordingly, it is important that swing assembly  70  be securely maintained in its upright, first position when the wheel chair drive assembly is in use. This secure maintenance of the first position is achieved in the depicted embodiment by a locking lever  86 , best seen in  FIG. 9 . Locking lever  86  slides forwards and backwards and its rearward aspect is maintained in horizontal forward and back sliding engagement with battery mount  34  by sliding arm mount  88 , which forstalls undesirable upwards and downwards movement of locking arm  86 . The locking arm  86  is biased towards maintaining engagement with lock arm notch  84  by a spring  87 . A locking arm release lever  90  is pivotedly attached to a frame  12  at pivot  92  and operated by a user with locking arm release lever handle  94 .  
         [0062]      FIG. 16  depicts one swing assembly or caster lever mounting bracket  100 .  FIGS. 6, 7  and  8  depict the mounting brackets fixedly attached to wheel chair. Attachment devices, such as two U-bolts and their respective nuts are used to attach each mounting bracket  100  to the frame of the standard wheel chair. Alternative through holes (not shown) in mounting bracket  100  provide for the adaptability of mounting bracket  100  for attachment to a variety of standard wheel chair frames design.  
         [0063]     The mounting bracket has a forward extension  110  which serves as a guide for assisting the engagement of the horizontal bar  78  of swing assembly with the mounting brackets. Because the guide flanges  110  are angled to be progressively wider at their forward aspect, the mounting bracket is able to receive the horizontal bar  78  from a range of directions. Accordingly, ease of engagement of the drive apparatus  10  with a wheel chair is achieved.  
         [0064]     Mounting bracket  100  is designed with an engagement face  120  which is substantially at right angles to the side portion of mounting bracket  100  whereon the mounting U-bolts are attached. This engaging face  120  serves as a rearward stop for horizontal bar  78  during engagement. Towards the bottom of the mounting bracket  100  the engagement face  120  is configured with a rear stop engagement face  122 , bottom support weight supporting face  124 , forward locking face  126  and entry face  128 . Together these components  122 - 126  comprise an engagement seat for horizontal bar  178 . For a secure seat, the internal dimensions of faces  122 ,  124  and  126  are dimensioned to closely cooperate with the external faces of horizontal bar  78 . Guide face  128  serves to guide horizontal bar  78  into seat  130  as it is being engaged with the wheel chair for operation.  
         [0065]     Engagement operation is executed by setting up the wheel chair drive apparatus  10  on the ground, just in front of the wheel chair. With the wheel chair occupant in the wheel chair and the control shaft  40  in its upwards position, drive wheel  20  is held turned  900  to act as a brake. Swing assembly  70  is in its second “out” position with the casters engaged with the ground. In the second position of swing assembly  70  maintains the handle  18  of installed battery housing  14  at a first level. This first level is lower than the level of the wheel chair cross bars in a standard wheel chair. The wheel chair occupant manually moves his wheel chair forward until guide flanges  100  engage the rearwardly projecting horizontal bar  78  and guide it towards seat  130 . When the horizontal bar  78  touches rear engaging face  122 , continued forward motion of the wheel chair will cause swing assembly  70  to rotate in a clockwise direction as shown progressively in  FIGS. 6, 7  and  8 . The wheel chair drive of apparatus  10  is held against being pushed forward by the drive wheel, which is turned 90°. With further forward motion, horizontal bar  78  is pushed downwards so that the bottom of horizontal bar  78  progresses towards its seat against bottom engaging face  124 . Swing assembly  70  continues to pivot clockwise direction until it rotates upwards into a substantially right angle to battery mounting rail  34 . The locking notch  84  engages the lock slide  86  and pushes it forwards until lock slide spring  87  biases lock slide  86  into notch  84  and holds the swing assembly  70  in its right angle, first position. Simultaneously with this motion, the battery mounting brackets will be raised upwards. Along with the battery mounting rails being raised, battery  14  and its handle are raised. Handle  18  is dimensioned such that when the swing assembly  70  is in its first position, handle  18  engages the cross bar to the wheel chair frame and holds them in a weight supporting position. Also simultaneously with the rotation of swing assembly  70 , casters  72  are rotated out of engagement with the ground.  
         [0066]     Casters  72 , being omni directional, operate with guide flanges  110  to facilitate an automatic mechanic adjustment of alignment as the swing assembly as the wheel chair and the mounting brackets are pushed into engagement with the swing assembly by the wheel chair operator.  
         [0067]     Alternatively, the driver can be installed by setting the wheel chair brakes and backing the drive apparatus under the chair under power, which actuates the same mechanisms as described above.  
         [0068]     Comparing  FIG. 12  with  FIG. 12A  illustrates that when the swing assembly  70  is out and casters  72  deployed, the rear end of the drive apparatus  10  is lower than its front. Consequently, the rear end of the delrin slide  19  on top of handle  18  is also lower than the x-frame member of the wheel chair, which allows the handle to slide under the x-frame easily. In  FIG. 12A , the swing assembly  70  is in, and also up, which raises the rear of the drive apparatus  10  and delrin slide  19  into lifting engagement with the wheel chair at the x-frame member.  
         [0069]     The weight supporting function of battery handle  18  is through its engagement with the cross bars of the wheel chair frame. This engagement is forward of the wheel chair&#39;s main wheels axle and forward of the center of gravity of the wheel chair with its occupant. Accordingly, raising of the wheel chair drive apparatus  10  by engagement of swing assembly  70  concomitantly raises the front casters of the wheel chair off the ground. This prevents interference of these wheels with the progress of the wheel chair with its bar style or main wheels or bar style or drive wheel  20  over minor obstacles. The wheel chair casters are only raised a small vertical distance however. Accordingly, they serve as anti-tip safety wheels or out riggers in the event of a sharp turn or hill or ramp that may otherwise threaten to tip the wheel chair and drive apparatus over.  
         [0070]     In view of the foregoing, it will be seen that the several advantages of the invention are achieved and attained.  
         [0071]     The embodiments were chosen and described in order to best explain the principles of the invention and its practical application to thereby enable others skilled in the art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated.  
         [0072]     As various modifications could be made in the constructions and methods herein described and illustrated without departing from the scope of the invention, it is intended that all matter contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative rather than limiting. For example, Thus, the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims appended hereto and their equivalents.