Abstract:
A chiropractic adjustment tool or tapper comprises a housing, the housing having an open end; a impact assembly disposed within the housing and secured thereto. The impact assembly comprises a reciprocating rod with adjustable travel and impact force. An impelling element such as a solenoid is provided to accelerate the reciprocating rod. Disposed on one end of the reciprocating rod is a coupler to permit multiple impact heads to be attached to the tool. The tool is further improved with the addition of a fan unit on a port in the housing and an exit port located on a distal end of the housing, preferably at a location such that air flow is across the impelling element, and any switch or circuitry to provide cooling and extend tool life.

Description:
BACKGROUND OF THE INVENTION 
     The present invention involves the field of medical devices. More particularly, it involves the field of percussive medical devices used as chiropractic adjustment tools used to move bones and relieve muscle spasms and stress. 
     Percussion is a new treatment modality for those who suffer from musculoskeletal pain and myofascial trigger syndrome. It is a non-surgical, non-invasive procedure that may serve as a therapeutic alternative to trigger point and epidural injections or be used when other treatments have failed. Performed on an outpatient basis, percussive treatment carries little or no risk and is relatively comfortable. 
     As is well-known in the chiropractic art, the spines or other bones of humans sometimes go out of alignment or are otherwise mis-adjusted. This can lead to discomfort and additional physical symptoms. In such cases an adjustment of the spine or other bone to a healthy alignment can have substantial therapeutic effects. 
     Several attempts have been made to provide hand-held or other small devices to assist in adjusting a patient&#39;s spine or other bone by the use of impacts. However, each of these devices provide limited force, are subject to failure, and have limited application and adjustability. 
     Needed in the field is a multiple impact device with easily adjustable impact pressure and impact heads. Also needed is a device with increased power, and cooling to extend device life. The present invention is directed to these shortcomings in the prior art. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention provides a chiropractic adjustment tool or tapper, which, generally, comprises a housing, with or without a handle and a motor or power source to drive an axially reciprocating rod. The reciprocating rod is disposed perpendicularly or near perpendicular to the handle. One end of reciprocating rod extends from the housing and on the extended end is a impact head with a coupler for the mounting of one or more impact heads. The other end of the reciprocating rod has a spring pair assembly to permit the ready adjustment of impact force and axial travel of the reciprocating rod. 
     A fan is affixed to the housing and air is used to cool the device with an inport and an outport on distal ends of the unit requiring air flow to transit heat generating components, including any motor, switches and circuitry. 
     The operation of the device is with a solenoid, or other motive force driving the reciprocating rod axially. The reciprocating rod is slideably mounted within the housing, transiting through the solenoid coil. The reciprocating rod is held in place by springs, affixed to the reciprocating rod to limit travel and to return the reciprocating rod to the neutral position between impacts. On activation, the reciprocating rod is accelerated axially by the solenoid. Mounted on the extended end of the reciprocating rod is one of a number of impact heads. An impact head is used to impact the patient&#39;s body. When the solenoid is reactivated, the reciprocating rod is again accelerated toward the patient&#39;s body. A typical rate of impact is twelve impacts per second. Both the speed and the force of impact are adjustable to provide optimal therapeutic effects. In a preferred embodiment, the travel and force of impact of the reciprocating rod is adjusted by adjusting the compression of the spring pair. 
     Improvement over the prior art is found in the reduction of the mechanical moving parts of the device, the use of the spring pair for adjusting impact force, the improved cooling of the device and the coupler to permit the use of multiple and adjustable impact heads. 
     Though the device may be used in a manner that provides continuous pressure punctuated by impacts, another improvement over the prior art is the use of an impact assembly that permits an impact head to provide instantaneous force without durational pressure. This is accomplished through the use of an accelerated reciprocating rod that is permitted to bounce or recoil off of the patient, providing impact force without pressure of any duration. This is advantageous as pressure is painful and increases bruising. 
     For a more complete understanding of the present invention, reference is made to the following detailed description and accompanying drawings. In the drawings, reference numbers refer to like parts through the several views. 
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
     FIG. 1 is an environmental view of an adjusting tool in accordance with the present invention with three different impact heads depicted; 
     FIG. 2 is a cutaway view of the impact tool depicting air flow. 
     FIG. 3 is a detail of the spring pair assembly. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to the drawings, there is depicted a chiropractic adjustment tool or tapper in accordance with the present invention, generally denoted at  10 . The tapper  10 , generally, comprises a housing  12 , a impact assembly  26  disposed within the housing, the impact assembly  26  comprising a motive source  14 , preferably a solenoid  14 , the motive source  14  providing operational power to the impact assembly  26  and a reciprocating rod  16  with an impact head  70  disposed at one end and secured to the reciprocating rod  16  by a coupler. At one end of the housing is an import  32  to permit air flow, and at a distal end, an outport  34  so positioned to permit air flow to transit the elements of the invention needing cooling such as the solenoid  14 , switches  28  and any circuitry  24 . A fan  36  is provided to increase airflow. Other methods of moving air, including membrane driven pumps may also be used. 
     The housing  12  is a hollow member having an outer surface  19  and an inner surface  21 . The housing  12  is made of any convenient material, such as plastic, metal, or the like. The housing  12  has a handle portion  23  to enable easy grasping and holding of the tapper  10 . The housing  12  also has a barrel portion  22  integral with the handle portion  23 . 
     Contained in the barrel portion  22  and affixed thereto is the motive source  14 , which in the preferred embodiment is a solenoid  14 . An improvement in the present invention is the use of a solenoid  14  with at least two coil elements comprising a first coil  42 , and a second coil  44  separated by an airspace  46  to permit improved cooling. 
     Transiting through the solenoid  14  is a reciprocating rod  16  responsive to the force generated by the solenoid  14  such that on activation the reciprocating rod  16  is accelerated axially. 
     An electric energy source is operatively connected to a switch  28 , preferably mounted in the handle portion  23 . The switch  28  is operatively connected to the solenoid  14  so that on activation, the solenoid  14  receives power. The switch  28  may be in any well-known form, including a “trigger” or a “button,” either of which plungingly closes the circuit to the power source. In the preferred embodiment, the circuit also contains additional circuitry  24  such as a relay or similar device to automatically activate and deactivate the solenoid  14  at an adjustable rate. 
     In the preferred embodiment, the reciprocating rod  16  is axially elongated and has a forward first end  18  on which is mounted a collar  62 , a medial portion  17  defined by an enlarged diameter portion which receives the motive force from the solenoid  14 , and a rearward second end  20  which is preferably threaded. The reciprocating rod  16  transits the barrel portion of the housing and the solenoid  14  contained therein. The reciprocating rod  16  exits two distal ends of the barrel portion of the housing. A coil spring pair  52 , placed in series, is disposed around the rearward end  20  of the reciprocating rod  16  with a forward spring  54  and a rearward spring  56 . 
     In the preferred embodiment, the rearward spring  56  is of a heavier gauge than the forward spring  54 . The forward spring  54  is disposed around the reciprocating rod  16  and held in place by an adjustable stop  57  placed in the reciprocating rod  16  on the forward end of the forward spring  54  and is biased against the inner surface of the housing  21  on the rearward end of the forward spring  54 . The rearward spring  56  disposed around the reciprocating rod  16  is biased against the outer surface of the housing  19  and fitted against a threaded annular head  58 . 
     The threaded annular head  58  is rotatably threaded onto the rearward end  20  of the reciprocating rod  16 . In operation the travel and force of the reciprocating rod  16  may be adjusted by tightening the annular head  58  and compressing the spring pair  52 . As the rearward spring  56  in the spring pair is heavier than the forward spring  54  of the spring pair, the forward spring  54  is compressed at a greater rate than the rearward spring  56 , causing the reciprocating rod  16  to draw back or be displaced towards the rear of the housing. The increased compression of the spring pair  52  and displacement of the reciprocating rod  16  adjusts axial travel of the reciprocating rod  16  when the solenoid  14  is activated. The spring pair  52  also provides the neutral position of the reciprocating rod  16  when not being impelled or accelerated by the solenoid  14 , such that on deactivation of the solenoid  14 , the reciprocating rod  16  recoils and returns to the neutral position as determined by the spring pair  52 . This provides the additional benefit of permitting the impact head  70  to impart force on the patient being treated without pressure of any duration. 
     In one embodiment, the adjustable stop  57  and the annular head  58  are marked with indicators to permit calibrated adjustments to the compression of the individual springs  54 ,  56 , in the spring pair  52 . This may be accomplished by moving the stop  57  to alter the compression of the forward spring  54  against the inner surface of the housing  21  independent of the adjustments of the annular head  58  which principally adjusts the compression of the rearward spring  56 . This permits added control over the force imparted by the impact head  70  on the patient, and also permits adjustment of the movement of the reciprocating rod  16 , slowing or adjusting the acceleration rate. 
     In use, the impact head  70  makes contact and imparts force only briefly on activation of the solenoid  14 , and then is immediately withdrawn and returned to the neutral position by the spring par  52 . The use of a solenoid  14  or similarly driven system permits the imparting of therapeutic force without any extended pressure. The benefit of the invention is obtained by the acceleration of the reciprocating rod  16 , and then permitting the reciprocating rod  16  to bounce or recoil on impact of the impact head  70  with the patient without any persistent pressure on the patient. In the preferred embodiment, acceleration is complete prior to impact. Extended pressure of any duration increases the likelihood of bruising. Avoiding extended pressure also permits higher levels of impact to be used without causing the patient pain. 
     When the power source  22  is engaged via the switch  28 , the solenoid  14  impels the reciprocating rod  16  forward to impact the patient. When the solenoid  14  is turned off or deactivated, the reciprocating rod  16  returns to the neutral position as determined by the spring pair  52 . The device may be set to provide for a single impact in activation, or with the use of a relay or similar circuitry  24 , a rate of impact may be established and adjusted by sequentially activating and deactivating the solenoid  14  once the power source is engaged. The switch  28  may be variable such that rate of impact increases with pressure on the switch  28 , or a second switch or dial (not shown) may be used to adjust the rate of impact. Such second switch may be located at the point of the outport  34  or another convenient location. 
     Affixed to the forward end  18  of the reciprocating rod  16  is a coupler. The coupler is used for affixing impact heads  70  of varying shapes. In the preferred embodiment the coupler is formed so as to permit the impact head  70  to be removably affixed to the reciprocating rod  16  at a set, but adjustable angle. This is accomplished through the use of a sleeve element  64  on the impact head  70 . The coupler is comprised of a collar  62  affixed to the reciprocating rod  16 , a collar pin  66  set on the collar  62  and pin notches  68  set in a sleeve base  67  of the sleeve element  64 . The collar  62  is mounted on the reciprocating rod  16  offset from the forward end  18  so as to permit the sleeve element  64  of the impact head to receive a portion of the forward end  18  of the reciprocating rod  16  for stability. The sleeve base  67  abuts the collar  62  and the collar pin  66  is received into one of a number of defined pin notches  68  on the sleeve base  67  so as to prevent rotation of the impact head  70 . A simple retaining hook or loop  72  or similar means retains the impact head  70 . 
     Depending on the positioning of the annular ring  58  on the reciprocating rod  16 , and the relative compression of the spring pair  52 , the reciprocating rod  16  is driven forward and forces one of the impact heads  70  mounted thereon to contact the person being treated at any of a range of rates, travels and force levels. The single or continuous series of impacts provides therapeutic treatment to the person being treated. 
     While the invention has been illustrated and described in detail in the drawings and the foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiment has been shown and described fully and that all changes and modifications that come within the spirit of the invention are desired to be protected.