Patent Publication Number: US-2006015127-A1

Title: Injection drill assembly

Description:
BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates generally to medical apparatuses, and more particularly to an injection drill assembly for an intra-osseous injection apparatus.  
      2. Description of the Related Art  
      A conventional intra-osseous injection apparatus, which is commonly used in drilling bones or teeth and further delivering an anesthetic or other fluids into other parts of a living body, either human or animal, includes a drill member  100  and a driving mechanism (not shown). The drill member, as shown in  FIG. 1 , has a needle  110  and a sleeve  120 . The sleeve  120  has a tunnel  121  longitudinally running therethrough and a hole  122  located at a peripheral wall thereof for communicating with the tunnel  121 . The needle  110  is inserted into the sleeve  120  and an adhesive, such as ultraviolet cured resin or hot glue, is put into the hole to fill space between the needle  110  and the sleeve  120 , such that the needle  110  and the sleeve  120  are fixedly connected with each other. However, the adhesive has to be sticky enough to fix the needle  110  to the sleeve  120  such that the production cost is increased. In addition, if the intra-osseous injection apparatus is operated for a long time or in high-temperature environment, the adhesive is subject to degeneration to incur separation of the needle  110  from the sleeve  120 .  
     SUMMARY OF THE INVENTION  
      The primary objective of the present invention is to provide an injection drill assembly for an intra-osseous injection apparatus; the injection drill assembly is structurally tight to prevent a needle from separation from a needle hub.  
      The secondary objective of the present invention is to provide an injection drill assembly for an intra-osseous injection apparatus; the injection drill assembly can be automatically assembled by machine to enhance the production efficiency.  
      The foregoing objectives of the present invention are attained by the injection drill assembly, which includes a needle, a needle hub, and a clamp. The needle hub includes a first section, a second section located behind the first section, and a tunnel longitudinally running therethrough. The first section has two annular ridges formed respectively at two ends thereof, and a body portion between the two annular ridges. The needle is inserted through the tunnel of the needle hub. The clamp is fitted onto the body portion of the needle hub to squeeze and tightly clamp the first section of the needle hub to further fixedly clamp the needle. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a perspective view of the prior art;  
       FIG. 2  is an exploded view of a first preferred embodiment of the present invention;  
       FIG. 3  is a perspective view of the first preferred embodiment of the present invention;  
       FIG. 4  is an exploded view of a second preferred embodiment of the present invention;  
       FIG. 5  is a perspective view of the second preferred embodiment of the present invention; and  
       FIG. 6  is a cross-sectional view taken from a line  6 - 6  indicated in  FIG. 5 .  
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
      Referring to  FIGS. 2 and 3 , an injection drill assembly  1  constructed according to a first preferred embodiment of the present invention includes a needle  10 , a needle hub  20 , and a clamp  30 .  
      The needle  10  is an elongated hollow member, having a beveled cutting end  11  at a front end thereof for delivering an anesthetic into the human or animal body while drilling through any of the bones or teeth.  
      The needle hub  20  is an elongated hollow member made of a flexible material, which has a low rigidity, including a first section  21 , a second section  22  located behind the first section  21 , and a tunnel  23  longitudinally running through the first and second sections  21  and  22  for inserting the needle  10 . The tunnel  23  has the same diameter as the needle  10  for tightly inserting the needle  10 . The first section  21  has two annular ridges (first annular ridge  211  and second annular ridge  211 ′) formed at two ends thereof, and a body portion  212  located between the two annular ridges  211  and  211 ′. The annular ridge  211  is tapered to have a decreasing diameter from a front end thereof to a rear end thereof. The diameter of the rear end of the annular ridge  211  is identical to the second section  22  to facilitate the clamp  30  to pass through the annular ridge  211 . The second section  22  can be connected with an intra-osseous injection apparatus (not shown) for synchronic rotation with the intra-osseous injection apparatus (not shown). Alternatively, the body portion  212  has a thin sidewall.  
      The clamp  30  is a hollow member made of a flexible material, such as plastic, having an inner diameter, which is slightly smaller than an outer diameter of the body portion  212 , smaller than that of the front end of the annular ridges  211  and that of the annular ridge  211 ′, and larger than that of the second section  22 , and having the same length as the body portion  212 . The clamp  30  is fitted onto the body portion  212  to tightly squeeze and clamp the body portion  212  of the first section  21  of the needle hub  20  and is fixedly located between the two ridges.  
      While assembling the injection drill assembly  1 , insert the needle  10  through the tunnel  23  of the needle hub  20 , and then put the clamp  30  to pass through the second section  22  and the annular ridge  211  abutting the second section  22  and to further be fitted onto the body portion  212  between the two ridges  211  and  211 ′ of the needle hub  20 . Because the clamp  30  is made of flexible material and the annular ridge  211  is tapered, the clamp  30  can slightly deformably pass through the ridge  211  abutting the second section  22  though the diameter of the front end of the ridge  211  is larger than the inner diameter of the clamp  30 . Because the inner diameter of the clamp  30  is smaller than the outer diameter of the body portion  212  and the needle hub  20  is made of the material of low coefficient of elasticity, low rigidity, and small moment of inertia of area, when the clamp  30  is fitted onto the body potion  212 , the body potion  212  can be deformably compacted by the clamp  30  to further tightly clamp the needle  10 . The inner diameter of the clamp  30  is smaller than that of the front end of the ridges  211  and that of the ridge  211 ′ of the needle hub  20 , such that when the clamp  30  is fitted onto the body portion  212 , the two ridges  211  and  211 ′ can prevent the clamp  30  from moving out of the needle hub  20  to further keep the clamp  30  fixedly tightly clamping the body portion  212  of the needle hub  20 .  
      Referring to  FIGS. 4-6 , the injection drill assembly  2  constructed according to a second preferred embodiment of the present invention includes a needle  40 , a needle base  50 , and a needle hub  60 .  
      The needle  40  is substantially identical to that of the aforementioned preferred embodiment.  
      The needle base  50  is a hollow member made of flexible material, which has a low rigidity, having a first tunnel  51  running therethrough for inserting the needle  40 , a head portion  52 , and a body portion  53  formed behind the head portion  52 . The first tunnel  51  has a diameter identical to that of the needle  40  for tightly inserting the needle  40 . The body portion  53  is non-circular tubular member, which cross-section can be triangle, quadrangle, or other polygon. The head portion  52  has an annular wedge portion  521 , which outer diameter is larger than that of the head portion  53 . Alternatively, the body portion  53  has a thin sidewall.  
      The needle hub  60  is an elongated hollow member made of flexible material, such as plastic, having a second tunnel  61  running therethrough for inserting the needle  40 , an annular incision  62  formed at a front end thereof for engaging the annular wedge portion  521  of the needle base  50 , and a main body  63  for connected with the intra-osseous injection apparatus (not shown). The second tunnel  61  is provided with a first section  611  and a second section  612  located behind the first section  611 . The second section  612  has a diameter identical to that of the needle  40  for tightly inserting the needle  40 . The first section  611  is tapered to have a decreasing diameter from a front end thereof to a rear end thereof. The diameter of the rear end of the first section  611  is larger than that of the second section  612  and smaller than that of the body portion  53 . The diameter of the front end of the first section  611  is identical to that of the body portion  53  of the needle base  50 . The first section  611  has a non-circular cross-section, which can be triangle, quadrangle, or other polygon corresponding to that of the body potion  53  for ensuring synchronic rotation of the needle base  50 , the needle hub  60  and the needle  40 , being as long as the body portion  53 .  
      While assembling the injection drill assembly  2 , insert the needle  40  through the first tunnel  51  to be tightly jammed with the needle base  50 , and then insert the needle base  50  into the second section  612  of the second tunnel  61  to enable the wedge portion  521  to engage the annular incision  62  of the needle hub  60 . While needle base  50  is inserted into the needle hub  60 , the body portion  53  of the needle base  50  can be deformably squeezed by the first section  611  to be further tightly fitted into the first section  611  of the second tunnel  61  of the needle hub  60 , such that the needle  40  can be fixedly clamped. When the injection drill assembly  2  is rotated together with the intra-osseous injection apparatus (not shown), the needle base  50  will not separate from the needle hub  60  and keep rotation together with the needle hub  60 .  
      In addition, the above procedures of the assembly are accomplished by machine, such that present invention can be automatically produced without manual checkout to further enhance the production efficiency.