Abstract:
A mounting for the head section of a chiropractic table that allows the practitioner to maintain a much greater degree of control over the various manipulations typically performed on the patient. The head support section has a cushion that is mounted for slideable movement along the longitudinal axis of the table which coincides with the patient&#39;s spine. A linkage arrangement allows the proximal end of the cushion to remain substantially the same distance from the chest lumbar section of the table as the head section is tilted downwardly. This allow a controlled flexion movement of the patient&#39;s cervical spine. The amount of gap and thus the amount of flexion can be adjusted by adjusting the linkage that is a part of the head section structure. In addition, the slideable movement of the head cushion longitudinally allows the practitioner to apply traction to the patient&#39;s spine with or without flexion, if such a movement is determined to be desirable.

Description:
BACKGROUND OF INVENTION 
     There are known and commercially available to practicing chiropractors and other health practitioners numerous types of tables to assist them in conducting examinations, adjustments and treatments beneficial to a patient. When such tables are used for chiropractic adjustments, the tables are commonly designed so that the patient support is separated into separate sections for the head, chest, lumbar, pelvic and foot sections. Typically, each of these sections is independently supported on a frame, and some of the sections are moveable in ways that permit the health practitioner to conduct the desired adjustment or treatment. For example, some of the sections are constructed with a mechanism that allows the section to be displaced a predetermined distance or pivoted a predetermined amount to facilitate a particular adjustment performed by the health practitioner. 
     The head section of chiropractic tables is typically designed and mounted so that it can produce one or more motions. For example, some head sections are mounted so that they can pivot as a unit in a curved path about an axis extending longitudinally along the patient&#39;s spine so that the health practitioner can impart a twisting motion on the patient&#39;s head and thus make a rotation adjustment. In addition, the head section is typically mounted on a vertical pivot at its proximal end so that the distal end can be swung from side to side which permits the health practitioner to perform a lateral flexion of the patient&#39;s head. Other tables are also pivotally mounted at the proximal end for movement about a horizontal axis so that the distal end at the top of the patient&#39;s head can be tilted upwardly and downwardly to provide a flexion adjustment. In addition, some tables provide for movement of the patient&#39;s head linearly along the spine to stretch a cervical portion of the spine and thereby induce traction on the patient&#39;s cervical spine. 
     In those tables where the head section is mounted for pivotal movement about a horizontal axis so that the distal end can be tilted upwardly and downwardly to produce flexion of the patient&#39;s cervical spine, the distance between the proximal end of the head section cushion and the adjoining chest-lumbar section will increase as the distal end of the head section tilts downwardly. Since the patient&#39;s trunk does not move, this gap can produce excessive flexion on the patient&#39;s spine and more flexion than the health practitioner wishes to produce. It can also produce traction even when the practitioner does not wish to induce traction on the spine. 
     Tables that are known in the prior art thus deprive the chiropractor or other practitioner with a lack of control over the amount of flexion that the practitioner has determined is desirable to treat the patient&#39;s condition. Also, the known designs of chiropractic tables provide only for the pivotal movement of flexion, and if the practitioner wishes to also apply traction to the patient, the practitioner must grasp the patient&#39;s head and lift it from the head section and apply traction directly. The head sections of known chiropractic tables do not provide for movement of the head section to allow both traction and flexion to occur using the same table. 
     Therefore there is a need for an improved chiropractic table which has a head section that allows the practitioner to perform a variety of manipulations more easily and more controlled than allowed on known chiropractic tables. 
     SUMMARY OF INVENTION 
     The invention provides a mounting for the head section of a chiropractic table that allows the practitioner to maintain a much greater degree of control over the various manipulations typically performed on the patient. The head support section therefore has a cushion that is mounted for slideable movement along the longitudinal axis of the table which coincides with the patient&#39;s spine. With the linkage arrangement described in detail hereinafter, the proximal end of the cushion will maintain a close position to the chest lumbar section of the table as the head section is tilted downwardly to allow a controlled flexion movement of the patient&#39;s cervical spine. This can be done either with or without applying traction to the patient&#39;s spine. The amount of gap and thus the amount of flexion can be adjusted by adjusting the linkage that is a part of the head section structure. In addition, the slideable movement of the head cushion longitudinally allows the practitioner to apply traction to the patient&#39;s spine with or without flexion, if such a movement is determined to be desirable. 
    
    
     BRIEF DESCRIPTION OF DRAWINGS 
     FIG. 1 is a perspective view of a chiropractic table having multiple, independent sections; 
     FIG. 2 is an exploded perspective view of the mounting structure for the head section of the table; 
     FIG. 3 is a side elevational view of the head section; 
     FIG. 4 is a top or plan view of the head section with the cushion removed; 
     FIG. 5 is an end view of the head section; 
     FIG. 6 is a side elevational view of the head section and illustrating the head section in a tilt up position; and 
     FIG. 7 is a side elevational view of the head section similar to FIG. 6 but showing the head section in tilt down position. 
    
    
     DETAILED DESCRIPTION 
     The invention relates to and is employed in connection with a patient support such as a table which is used for the examination or treatment of the patient. The preferred embodiment is described in connection with a chiropractic table that has separate and typically independently moveable patient support sections. Referring to FIG. 1 of the drawings, there is illustrated a chiropractic table which has a table frame  10  supported by legs  12 . At the head of a table is a head section indicated generally by the reference numeral  14  which has a cushion  16  mounted on supports  18  (FIG.  3 ). The head section  14  is mounted on the table frame  10  in the manner described hereinafter. The table also includes a chest-lumbar section  20 , a pelvic section  22 , and a foot section  24 . As is well known to those skilled in the art, each of the sections  20 ,  22  and  24  are secured to the table frame  10  in any suitable manner depending upon the particular table and the purposes for which it is specifically designed. 
     Referring now to FIGS. 2,  3 ,  4  and  5 , the head section  14  is shown in detail. As best seen in FIGS. 3,  4  and  5 , the table frame  10  includes a horizontal support bar  26  with two forwardly extending support arms  28  to which is pivotally mounted a T-shaped support block  30 . Block  30  has a downwardly extending pivot rod  32  (FIG. 2) that turns within a sleeve  34  therefore providing for swinging movement of the entire head section  14  from side to side if the practitioner desires to apply lateral flexion. The T-shaped support block  30  is also secured to the supports arms  28  for vertical pivoting movement about a pivot axle  36  that is secured to the support arms  28 . 
     Secured to and extending forwardly from the T-shaped support block  30  are guide members such as a pair of laterally spaced apart guide rods  38 . Rods  38  may be secured to the support block  30  by fasteners  40 . The outer or distal ends of the guide rods  38  are secured to a lock frame assembly indicated generally by the reference numeral  42 . Mounted on the guide rods  38  is a slide bracket assembly  44  which includes a front member  46  and a rear member  48  which is rigidly joined to the front member  46  by side members  50 . Members  46 ,  48  and  50  form a rigid rectangular frame which has openings  52  extending through the rear member  48  and openings  54  extending through the front member  46 . Openings  52  and  54  are in alignment to receive the guide rods  38 , thus providing for slideable movement of the slide bracket assembly  44  back and forth along the guide rods  38 . 
     Extending upwardly from the rear member  48  of the slide bracket assembly  44  is a vertical support  56 . Similarly, an L-shaped vertical support  58  is affixed to the front member  46 , and support member  58  has a leg  60  extending upwardly. The vertical support  56  and leg  60  provide a mounting for the cushion  16  and its supports  18 . The particular manner of mounting the cushion  16  and supports  18  to the slide bracket assembly  44  is not shown in detail since it forms no part of the invention and is well known to those skilled in the art. However, typically the supports  18  would be mounted in a suitable manner on the vertical support  56  and the leg  60  so as to provide for a swinging motion of the cushion  16  in the event the practitioner wishes to apply rotation to the head of the patient. It will be understood by those skilled in the art that this rotation movement is applied by swinging the cushion  16  in a curved path about an arc that is represented by the concave surface  62  formed in the rear member  48  of the slide bracket assembly  44 . Motion of this type is illustrated in U.S. Pat. No. 4,732,141 as applied to a chest-lumbar section. 
     The lock frame assembly  42  includes a rocker arm  64  that has a transverse slot  66  and a forwardly extending locking arm  68 . The rocker arm  64  is pivotally attached to support arms  70  of frame assembly  42  by means of a suitable fastener  72  and roller bearing  74 . A linkage bar  76  is slideably engaged with a lock block  78  which in turn is attached at a selected position in the slot  66  of the rocker arm  64  by a locking fastener  80  and bushing  82 . The linkage bar  76  is locked inside of the lock block  78  by a lock bolt  84 . The linkage bar  76  must be locked to the lock block  78  during tilting of the head section  14  to induce flexion to the patient. The proximal end of the linkage bar  76  is pivotally attached to the rear member  48  of the slide bracket assembly  44  by a suitable fastener  86  and bushing  88 . 
     As best seen in FIGS. 3 and 4, a push rod  92  has its proximal end pivotally connected to the frame support bar  26  and the other end pivotally connected to the rocker arm  64  by fastener  93 . As best seen in FIGS. 4 and 5, the push rod  92  is curved to produce the desired push-pull action on the rocker arm  64  as described hereinafter. To provide for return of the head section to its normal position, a return spring  90  has one end attached to the rocker arm  64  while the proximal end of the spring  90  has its other end attached in any suitable manner to the T-shaped support block  30 . 
     As indicated above, the rocker arm  64  which forms a part of the lock frame assembly  42  is pivotally moveable about the roller bearing  74 . To lock the rocker arm  64  in a selected position and thus prevent the head section  14  from tilting, a lock knob  94  at the outer end of the locking arm  68  controls the movement of a locking pin  97  that slide in the locking arm  68  into and out of engagement with the curved locking member  96 . The curved surface of the locking member  96  is preferably formed from a ring gear to provide a positive lock with the locking pin  97 , which pin  97  is biased into a locking position by spring  98 . The locking member  96  also provides for locking the head section  14  at any desired degree of tilt. 
     The operation of the head section  14  will now be described. When the practitioner desires to produce controlled flexion on a patient lying on the table with his or her head resting on the cushion  16  of the head section  14 , the practitioner first determines the amount of tilt of the head section  14  depending upon the amount of flexion of the patient&#39;s cervical spine that is desired. The adjustment of the amount of flexion is made by loosening the locking nut  80  and positioning the lock block  78  in the desired position in slot  66  of the rocker arm  64 . By moving the lock block  78  closer to the pivot of the rocker arm  64  provided by the roller bearing  74 , the amount of downward tilt of the head section  14  will be decreased. On the other hand, by moving the lock block  78  farther from the pivot of the rocker arm  64  provided by the roller bearing  74 , the amount of downward tilt of the head section  14  will be increased. By first pulling out the lock knob  94  to release the locking pin  97  from the locking member  96  and the then pressing down on the distal end of the head cushion  16 , the push rod  92  will push the rocker arm  64  against the resistance of spring  90 . Through the action of the linkage bar  76  which is joined to the slide bracket assembly  44 , the slide bracket assembly  44  will move upwardly on the guide rods  38  causing the head section  14  to remain substantially in the same position relative to the chest-lumbar section  20  as the head section tilts. Thus, the gap between the head section  14  and chest-lumbar section  20  will not widen. As indicated above, the amount of head-flexion/tilt of the head section  14  can be adjusted by releasing the locking fastener  80  and then positioning the lock block  78  relative to the pivot  74  of the rocker arm  64 . Regardless of the amount of tilt of the head section  14 , the gap between the head section  14  and chest-lumbar section  20  will not change. This thus prevents excessive flexion to be induced upon the patient&#39;s cervical spine and will prevent any undesired traction on the patient&#39;s spine from occurring. The action of the linkage when the head section  14  is tilted downwardly is illustrated in FIG.  7 . 
     If it is desired to tilt the head section  14  upwardly, this can also be done with the gap between the head section  14  and chest-lumbar section  20  being maintained. In other words, the cushion  16  on the head section  14  will not in any way interfere with the cushion on the chest-lumbar section  20 . This action is illustrated in FIG.  6 . When the head section  14  is tilted upwardly, the push rod  92  will pull on the rocker arm  64  which will pivot about the pivot point provided by fastener  72  thus causing the slide bracket assembly  44  to move outwardly on the guide rods  38  carrying with it the head section  14  which will be moved outwardly to maintain the gap between head section  14  and the chest-lumbar section  20 . 
     The mechanism of the invention also provides for controlled traction of the patient&#39;s cervical spine if the practitioner so desires. By first unlocking the linkage bar  76  from the lock block  78  by loosening the lock bolt  84 , the slide bracket assembly  44  is freed to slide on the guide rods  38 . Because of the sliding action of the slide bracket assembly  44  along the guide rods  38 , the practitioner can grasp the head section  14  and the patient&#39;s head and apply the desired traction. In other words, by releasing the lock bolt  84 , the head section  14  is free to move inwardly and outwardly along the guide rods  38 . 
     In all of the above actions, the return spring  90  will always return the head section  14  and cushion  16  to its normal position. 
     The mechanism of the invention can be used alone in the head section or it can be combined with any known structures. Thus, the mechanism of the invention does not interfere with known structures for producing rotation, lateral flexion or any drop or snap action. In other words, the mechanism of the invention can be used alone or combined with any known structures for producing one or more of the desired procedures. 
     Having thus described the invention in connection with the preferred embodiments thereof, it will be evident to those skilled in the art that various revisions can be made to the preferred embodiments described herein without departing from the spirit and scope of the invention. It is my intention, however, that all such revisions and modifications that are evident to those skilled in the art will be included within the scope of the following claims.