Abstract:
A safety lock for a clamp closing a therapeutic fluid conduit, the clamp comprising a clamping end and a locking end which wrap around a fluid conduit receiving space wherein, when in a clamped position, the locking end mates with the clamping end to maintain a clamping projection in the fluid conduit receiving space, the lock comprising a first attachment at a first end thereof, the first attachment being sized and shaped to receive therein a portion of the clamping end, the first attachment abutting the clamping projection to define a maximum travel of the lock along the clamping end toward the locking end and a second attachment at a second end thereof preventing the locking end from moving away from the clamping end.

Description:
PRIORITY CLAIM 
       [0001]    This application claims the priority to the U.S. Provisional Application Ser. No. 60/957,343, entitled “Clamp Safety Lock with Printable Area,” filed on Aug. 22, 2007. The specification of the above-identified application is incorporated herewith by reference. 
     
    
     BACKGROUND 
       [0002]    Catheters are commonly used to supply or withdraw fluids to internal areas of the body. Certain catheters are left in place to provide repeated access for such fluid transfers. In these cases, a proximal end of the catheter which remains accessible outside the body must be sealed between uses to prevent fluids from leaking out and contaminants from entering the body. 
         [0003]    Tubing clamps are used with many such catheters having proximal ends located at diverse parts of the body. As such catheters may be left in place for extended periods, the clamps may be accidentally opened (e.g., by patient activity). This may cause significant problems, such as infection due to foreign contaminants entering the catheter and contamination of external surfaces by bodily fluids. 
         [0004]    In addition, because of the many applications for catheters, it is often useful to provide information regarding the specific use of a catheter. As multiple catheters may be used on a patient for different purposes, easily distinguishing the catheters becomes important. 
       SUMMARY OF THE INVENTION 
       [0005]    In one aspect the present invention is directed to a safety lock for a clamp closing a therapeutic fluid conduit, the clamp comprising a clamping end and a locking end which wrap around a fluid conduit receiving space wherein, when in a clamped position, the locking end mates with the clamping end to maintain a clamping projection in the fluid conduit receiving space, the lock comprising a first attachment at a first end thereof, the first attachment being sized and shaped to receive therein a portion of the clamping end, the first attachment abutting the clamping projection to define a maximum travel of the lock along the clamping end toward the locking end and a second attachment at a second end thereof preventing the locking end from moving away from the clamping end. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0006]      FIG. 1  is a top view showing a clamp safety lock according to an embodiment of the present invention; 
           [0007]      FIG. 2  is a perspective view of the clamp safety lock shown in  FIG. 1 ; 
           [0008]      FIG. 3  is a side elevation view of the clamp safety lock shown in  FIG. 1 ; 
           [0009]      FIG. 4  is a side view showing the clamp safety lock according to the invention attached to a clamp; 
           [0010]      FIG. 5  is a perspective view of the clamp safety lock and clamp shown in  FIG. 4 ; 
           [0011]      FIG. 6  is a side view of the clamp safety lock shown in  FIG. 5  shown in the locked position; 
           [0012]      FIG. 7  is a side view of the clamp safety lock shown in  FIG. 5  shown in the disengaged position; 
           [0013]      FIG. 8  is a perspective view of a second embodiment of the clamp safety lock according to the invention; 
           [0014]      FIG. 9  is a perspective view of a third embodiment of the clamp safety lock according to the invention; 
           [0015]      FIG. 10  is a perspective view of a fourth embodiment of the clamp safety lock according to the invention; and 
           [0016]      FIG. 11  is a perspective view of a fifth embodiment of the clamp safety lock according to the invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0017]    The present invention may be further understood with reference to the following description and to the appended drawings, wherein like elements are referred to with the same reference numerals. The present invention relates to devices for closing the proximal ends of catheters and other medical tubes to prevent leaks and contamination by external materials. 
         [0018]    The exemplary embodiments of the present invention provide a safety clamp lock which assures that a clamp on the end of the catheter or other medical conduit remains closed despite forces applied accidentally thereto during normal patient activity. Many catheters have an end cap to prevent a catheter from completely opening when a clamp is accidentally opened. However, these caps are often insufficient to completely isolate the catheter. The safety lock according to the invention prevents the clamp from opening in the first place unless the safety lock has first been disengaged. The exemplary safety lock may be added to a clamp without modifying the clamp itself, thus making it useful for enhancing the utility of a wide range of existing devices. 
         [0019]    In addition, the safety lock according to embodiments of the invention comprises at least one display area on which information may be displayed for presentation to a user. For example, a planar display area may be provided on which information may be printed or otherwise displayed. Printed, etched or molded writing, symbols, drawings, etc. may be applied to the display regions of the safety lock. The display regions are preferably oriented so that, when in place on a catheter, they are visible to a person operating the clamp and the safety lock. 
         [0020]    As shown in  FIGS. 1 ,  2  and  3 , a safety lock  100  according to an exemplary embodiment of the invention is ergonomically shaped to facilitate grasping by a user for placement on a clamp to lock the clamp so that it can not be opened while the lock  100  is attached thereto as shown in  FIGS. 4 and 5 . It is not necessary to modify the conventional clamp in any way to use the safety lock  100 , thus increasing its usefulness. 
         [0021]    The safety lock  100  comprises an attachment band  102  connected by a body  110  to a engagement face  106  extending therefrom. The attachment band  102  forms a first attachment point to the clamp  150  and has dimensions sufficient to allow a locking end  152  of the clamp  150  to be inserted therethrough until the lock  100  is in place. For example, the locking end  152  is threaded through the attachment band  102 , until a clamping protrusion  156  abuts the attachment band  102 . As would be understood by those skilled in the art, the locking end  152  is designed to engage a clamping end  154  to retain the clamp  150  in a closed configuration over a catheter or other medical conduit which extends through an opening  160  with the clamping protrusion  156  locking the locking end  152  in the closed position. In this position, the attachment band  102  is captured by the clamp  150  preventing removal of the safety lock  100  therefrom. 
         [0022]    The engagement face  106  of the safety lock  100  limits movement of the locking end  152  when the safety lock  100  is attached to the clamp  150 . It also provides a second attachment point of the lock  100  to the clamp  150 . More specifically, the engagement face  106  prevents the locking end  152  from moving away from the clamping end  154  preventing disengagement of the locking end  152  form the clamping end  154  while the lock  100  remains in place. The engagement face  106  comprises a protrusion  120  that reaches into the clamp  150  and extends into the slot  158 , to secure the position of the safety lock  100 . A raised area  108  projects from an end of the protrusion  120  to engage an edge of the slot  158 . As this raised area  108  slides over the edge of the slot  158 , the user receives tactile feedback providing an alert that the safety lock  100  is in the locked position over the clamp  150  (i.e., to the left in  FIG. 4 ). In the locked position as shown in  FIG. 6 , the lock  100  covers outer surfaces of the locking end  152  and the clamping end  154  deflecting items which might otherwise engage the end of the locking end  152  out of engagement with the clamping end  154 . In one embodiment of the invention as shown in  FIG. 11 , the lock  262  is biased so that, when in the locking position, a force is applied between the attachment band  264  and the engagement mechanism  268  drawing the locking end  152  toward the clamping end  154 . Alternatively, as would be understood by those skilled in the art, the bias of the lock  262  may be selected to resist flexing of the lock  100  away from the locking position. In the locking position shown in  FIG. 6 , the protrusion  120  engages the slot  158  preventing the engagement face  106  from being rotated counterclockwise as seen in  FIG. 7  to expose the locking and clamping ends  152 ,  154 , respectively. 
         [0023]    The body  110  comprises planar surfaces and rounded profiles arranged to follow contours of the clamp  150  with an inner surface of the body  110  contoured to lie generally along an outer surface of the clamping protrusion  156  when the safety lock  100  is in the locked position over the clamp  150  while the engagement face  106  lies over and covers the portion of the lock extending from the locking end  152  to the slot  158 . The body  110  also comprises geometrical features that facilitate disengaging the lock  100  including, for example, a step  122  providing an abutment surface on the body  110  which a user may engage to push the safety lock  100  (to the right in  FIGS. 6 and 7 ) while pushing the engagement face  106  away from the locking end  152  to disengage the raised area  108 . This releases the protrusion  120  from the slot  158  allowing the attachment band  102  to move toward the clamping end  156  until the protrusion  120  clears the slot  158 . At this point, the lock  100  is disengaged and the clamp  150  may be opened in the usual manner by pushing the locking end  152  radially outward allowing the locking end  152  to spring free from the clamping end  154  as shown in  FIG. 7 . 
         [0024]    An additional feature of the body  110  may be used to assist in opening the clamp  150  when desired while disengaging the safety lock  100 . In the exemplary embodiment, a second step  124  may be formed on the underside of the body  110  which, when engaged on a clamp, faces an upper surface of the clamping end  154  abutting the locking end  152 . When the user desires to open the clamp  150 , a force is applied to the step  122  to slide the safety lock  100  toward the locking end  152  (to the right in  FIG. 6 ). As the body  110  moves in this direction, the second step  124  abuts the locking end  152  pushing it away from the clamping end  154 , helping to disengage the two components. The motion also disengages the safety lock  100  from the clamp  150 , as described above. 
         [0025]      FIG. 4  shows the safety lock  100  coupled to the clamp  150  in a disengaged position while the clamp  150  is closed and  FIG. 6  shows the safety lock  100  fully engaged on the closed clamp  150  while  FIG. 7  shows the lock  100  in the disengaged position while the clamp  150  is open. As shown in the exemplary embodiment of  FIG. 6  and described above, the engaged safety lock  100  is retained on the clamp  150  by the attachment band  102  and by the protrusion  120  which is received within the slot  158 . In this configuration, the edge  104  presses inward on or is against the clamping end  154 , while the engagement face  106  presses the locking end  152  toward the clamping end  154  keeping the clamping and locking ends  154 ,  152 , respectively, of the clamp  150  engaged with one another. Alternatively, once locked in place on a clamp  150 , the lock  100  may be configured so that it cannot be unlocked until a failure point of its structure is severed through the application of a predetermined force. The protrusion  108  may, for example, be in the shape of a barb that will slide in the slot  158  but which cannot be easily removed without deforming the barb. Alternatively as shown in  FIG. 11 . features  268  may be formed in the shape of a barb so that once the features  268  engage the feature  152  of the clamp  150  the force required to disengage the features  268  therefrom will deform and render unusable the features  268  on the safety lock  262 , indicating that the clamp  150  may have been opened. 
         [0026]    After the safety lock  100  has been translated to the right into the disengaged position, the clamp  150  may be opened in the usual manner as shown in  FIG. 7  and the safety lock  100  may then be removed from the clamp  150 . As described above, the opening of the clamp may be made simultaneous with the opening of the lock  100  because, as the lock  100  is moved toward the locking end  152 , the protrusion  120  is freed from the slot  158  and the second step  124  displacing the engagement face  106  from the locking end  152  and releasing the locking end  152  from the clamping end  154 . In this position only the attachment band  102  retains the safety lock  100  on the clamp  150  and the lock  100  may be removed from the clamp  150  by threading the locking end  152  out of the attachment band  102  in an action reverse that used to engage the two components. 
         [0027]    The safety lock  100  is preferably provided with several flat surfaces that may be advantageously used to display graphical information. In the exemplary embodiment, the safety lock  100  comprises two substantially planar display surfaces  112 ,  114  formed on the body  110 . The display surfaces  112  and  114  form a printable area of the safety lock  100 , such that graphical information may be printed, etched molded or applied thereon. The graphical information may include, for example, written instructions, warnings, diagrams, drawings, color coding and any other information. 
         [0028]    According to the invention, various modifications may be carried out on the safety lock to address specific needs. For example, as shown in  FIG. 8 , additional printable areas may be provided on the safety lock  200 . In this embodiment, two display surfaces  202 ,  204  corresponding to the display surfaces  112 , 114  if the lock  100  are arranged on the body  210  of the lock  200  and are supplemented by additional display surfaces  206 ,  208  oriented along a plane different than that of the display surfaces  202 ,  204 , so that they are visible from different angles. 
         [0029]    For example,  FIG. 9  shows a safety lock  220  comprising a body  222  having two substantially planar portions  228 ,  230  joined by a substantially straight segment  232  rather than the curved segment of previously described embodiments. This embodiment may be easier and less expensive to manufacture, among other advantages. For example, the section  232  may be used to display additional communications and/or may act as a spring device maintaining the protrusion  120  engaged with the slot  158 . The exemplary embodiment shown in  FIG. 9  retains the edge  224  and the second step  226 , which in this case ramps gradually away from the portion  230  at an obtuse angle. 
         [0030]    As shown in  FIG. 10 , a lock  240  according to a further exemplary embodiment may be attached to a clamp after the tubing (such as a catheter body) has been placed therethrough. For example, a first end of the safety lock  240  may be connected to a first end the clamp by an engagement face  244  with a protrusion  246  which is received within a slot of the locking end of a clamp, as described above. On the opposite end, the attachment band  102  of the previous embodiments is replaced by a pair of legs  248  with protrusions  250  extending laterally inward therefrom to engage edges of the clamp. The legs  248  and the protrusions  250  allow the lock  240  to be snapped in place over the clamp without having to thread the clamp through a slot as with the attachment band  102 . Thus, the lock  240  may be put in place on a clamp which has already been closed around a conduit. 
         [0031]    As shown in  FIG. 11 , a lock  260  according to a further embodiment of the invention includes an alternative mechanism for attaching to the locking end  152  of a clamp  150 . The lock  260  includes an attachment band  264  similar to that in the above described embodiments at a first end of a body  262  thereof. The second end of the body  262  includes attachment members  268  extending therefrom for gripping around the locking end of the clamp in a manner similar to the manner in which the legs  248  and the protrusions  250  of the lock  240  grip the clamping end of the clamp. The attachment members may, for example, comprise snaps or detents which pass around the sides of the locking end and lock the lock  240  thereto. If barbs are used, the lock  260  would better keep the clamp closed. If detents are used, the lock  260  would enhance the clamp&#39;s ability to remain closed. A feature  268  formed in the shape of a barb may be more easily engaged with the feature  152  of clamp  150  but requires increased force to be disengaged therefrom. If feature  268  is of a rounded shape (detent) the same force would be used to engage and disengage feature  268  to feature  152  of clamp  150 . Those skilled in the art will understand that an alternative lock design may employ a first end including legs and protrusions similar to the legs  248  and the protrusions  250  of the lock  240  with a second end as shown in the embodiment of  FIG. 11 . 
         [0032]    The present invention has been described with reference to specific exemplary embodiments. Those skilled in the art will understand that changes may be made in details, particularly in matters of shape, size, material and arrangement of parts. Accordingly, various modifications and changes may be made to the embodiments. The specifications and drawings are, therefore, to be regarded in an illustrative rather than a restrictive sense.