Patent Document

CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit under 35 U.S.C. §119(e) to U.S. Provisional Patent Application Ser. No. 61/880,174, titled: “Collapsible Drill and Associated Methods of Use”, filed on Sep. 19, 2013, the disclosure of which is incorporated herein by reference in its entirety. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates to collapsible drills and associated methods of use and, in particular, to collapsible drills which prevent spinning and/or advancing of a drill bit upon penetration of a drilled material. 
     BACKGROUND 
     Drilling holes within structures can be a common requirement in both medical and industrial fields. For example, in medical fields, drilling a hole through cartilage and/or bone may be desired. As a further example, in industrial fields, drilling a hole through wood, brick, steel and/or drywall may be desired. In general, a standard drill with a drill bit can be utilized to create the desired hole in the structure or material. Some traditional drills include a drill bit secured with a chuck which can be spun by a motorized system. Thus, any force or linear translation applied to the drill can be transferred directly to the drill bit. 
     Although the standard drill can be utilized successfully in sonic scenarios, in other scenarios, the depth of penetration of the drill bit in the structure or material can be critical. For example, in medical fields, structures such as blood vessels and/or nerves can exist behind the cartilage and/or bone being drilled and inadvertent injury to these structures can be catastrophic, e.g., vascular injury, neurologic damage, and the like. Similarly, in industrial fields, structures such as electrical wires can exist behind the material being drilled and inadvertent injury or penetration to these structures can be catastrophic or harmful to the user, e.g., electrocution injury, and the like. Thus, an inadvertent “plunging” of the drill bit, e.g., the drill bit traveling beyond the material being drilled, could lead to injury of the structures behind the material being drilled by the spinning drill bit itself and/or through direct penetration of the structure. 
     Traditionally, prevention of such injuries has been to allow the drill bit to travel only a fixed or predetermined distance, e.g., by utilizing a drill press or a similar device. However, in this method, the thickness of the material being drilled must be accurately known. In many scenarios, the thickness of the material being drilled may not be known to the user, e.g., drilling dry wall, or may be variable, e.g., curved bone. Thus, a common scenario involves drilling blindly whereby the distal surface, e.g., the inner surface, of the material being drilled is not visualized by the user. Therefore, the thickness of the material, e.g., the thickness of the bone, the current depth of penetration of the material by the drill bit and/or the structures behind the material being drilled, e.g., blood vessels, nerves, electrical wires, and the like, are not known. 
     Thus, a need exists for drills and associated methods which prevent spinning and/or advancing of a drill bit upon penetration of a structure. A further need exists for a drill and associated methods of use which retracts the drill bit of the drill away from the structures beyond the material being drilled upon penetration of the material. These and other needs are addressed by the collapsible drill and associated methods of use presently disclosed. 
     SUMMARY 
     The present disclosure provides exemplary collapsible drills and associated methods of use. Thus, in one aspect, the disclosure provides a collapsible drill including or comprising a chuck, a piston and a motor section. In an exemplary embodiment, the chuck is configured and dimensioned to receive a drill bit. In certain embodiments, the piston includes a pair of interlocking splines. In additional embodiments, the motor section drives rotation of the piston and the chuck. In some embodiments, depression of the piston stops rotation of the chuck relative to the piston. 
     In any of the embodiments described herein, the piston includes a piston rod linearly translatable within a cylinder. In some embodiments, the pair of interlocking splines includes a plurality of grooves on the cylinder configured to interlock or engage with a plurality of complementary teeth on the piston rod. In certain embodiments, the pair of interlocking splines includes a plurality of teeth on the cylinder configured to interlock or engage with a plurality of complementary grooves on the piston rod. 
     In additional embodiments, the piston rod includes a radial protrusion extending therefrom. In some embodiments, the cylinder includes an inner ledge configured and dimensioned to mate with the radial protrusion of the piston rod. In certain embodiments, the collapsible drill includes a seal, e.g., an O-ring, positioned between the radial protrusion and the inner ledge to form a sealed chamber within the cylinder. 
     In certain embodiments, the motor section includes a mechanism for filling the sealed chamber within the cylinder with compressed air. In certain embodiments, the motor section includes a mechanism for venting compressed air from the sealed chamber to atmosphere. In some embodiments, venting the compressed air from the sealed chamber to atmosphere depresses the piston rod into the cylinder. In additional embodiments, depressing the piston rod into the cylinder disengages the plurality of grooves and the plurality of complementary teeth of the pair of interlocking splines. In further embodiments, disengaging the plurality of grooves and the plurality of complementary teeth of the pair of interlocking splines stops rotation of the chuck relative to the piston, e.g., the cylinder of the piston. 
     In certain embodiments, depressing the piston rod into the cylinder automatically retracts the drill bit from the material. In some embodiments, the collapsible drill includes a second pair of interlocking splines positioned between the cylinder and the motor section. 
     In an additional aspect, the present disclosure provides exemplary methods of drilling into a material that include providing a collapsible drill as described herein. In certain embodiments, the exemplary methods include the step of driving rotation of the piston and the chuck with the motor section. In certain embodiments, the exemplary methods include depressing the piston to stop rotation of the chuck relative to the piston. 
     In additional embodiments, the exemplary methods include filling a sealed chamber within a cylinder of the piston with compressed air to position a radial protrusion extending from a piston rod against an inner ledge of the cylinder. In certain embodiments, the exemplary methods include maintaining a pressure within the sealed chamber to maintain the drill bit in an extended position. 
     In certain embodiments, the exemplary methods include interlocking or engaging a plurality of grooves on a cylinder of the piston with a plurality of complementary teeth on a piston rod of the piston of the pair of interlocking splines to drive rotation of the chuck relative to the piston. In certain embodiments, the exemplary methods include interlocking or engaging a plurality of teeth on a cylinder of the piston with a plurality of complementary grooves on a piston rod of the piston of the pair of interlocking splines to drive rotation of the chuck relative to the piston. 
     In additional embodiments, the exemplary methods include venting the sealed chamber to depress the piston rod into the cylinder. In some embodiments, depressing the piston rod into the cylinder further includes disengaging a plurality of grooves on the cylinder with a plurality of complementary teeth on the piston rod of the pair of interlocking splines. In some embodiments, depressing the piston rod into the cylinder further includes disengaging a plurality of teeth on the cylinder with a plurality of complementary grooves on the piston rod of the pair of interlocking splines. 
     In certain embodiments, disengaging the plurality of grooves on the cylinder with the plurality of complementary teeth on the piston rod of the pair of interlocking splines includes stopping rotation of the chuck relative to the piston. In certain embodiments, disengaging the plurality of teeth on the cylinder with the plurality of complementary grooves on the piston rod of the pair of interlocking splines includes stopping rotation of the chuck relative to the piston. 
     In certain embodiments, depressing the piston rod into the cylinder includes automatically retracting the drill bit from the material. 
     Other objects and features will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed as an illustration only and not as a definition of the limits of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       To assist those of skill in the art in making and using the disclosed collapsible drills and associated methods, reference is made to the accompanying figures, wherein: 
         FIG. 1  shows a side, partial cross-sectional view of an exemplary collapsible drill in an extended and engaged position prior to complete penetration of a drilled material; 
         FIG. 2  shows a detailed side, cross-sectional view of an exemplary collapsible drill in an extended and engaged position prior to complete penetration of a drilled material; 
         FIG. 3  shows a side, partial cross-sectional view of an exemplary collapsible drill in a collapsed and disengaged position after complete penetration of a drilled material; and 
         FIG. 4  shows a detailed side, cross-sectional view of an exemplary collapsible drill in a collapsed and disengaged position after complete penetration of a drilled material. 
     
    
    
     DETAILED DESCRIPTION 
     The following is a detailed description of the invention provided to aid those skilled in the art in practicing the present invention. Those of ordinary skill in the art may make modifications and variations in the embodiments described herein without departing from the spirit or scope of the present invention. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for describing particular embodiments only and is not intended to be limiting of the invention. All publications, patent applications, patents, figures and other references mentioned herein are expressly incorporated by reference in their entirety. 
     Where a range of values is provided, it is understood that each intervening value, to the tenth of the unit of the lower limit unless the context clearly dictates otherwise, between the upper and lower limit of that range and any other stated or intervening value in that stated range, is encompassed within the invention. Ranges from any lower limit to any upper limit are contemplated. The upper and lower limits of these smaller ranges which may independently be included in the smaller ranges is also encompassed within the invention, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits, ranges excluding either both of those included limits are also included in the invention. 
     The articles “a” and an as used herein and in the appended claims are used herein to refer to one or to more than one (i.e., to at least one) of the grammatical object of the article unless the context dearly indicates otherwise. By way of example, “an element” means one element or more than one element. 
     All numerical values within the detailed description and the claims herein are modified by “about” or “approximately” the indicated value, and take into account experimental error and variations that would be expected by a person having ordinary skill in the art. 
     The phrase “and/or,” as used herein in the specification and in the claims, should be understood to mean “either or both” of the elements so conjoined, i.e., elements that are conjunctively present in some cases and disjunctively present in other cases. Multiple elements listed with “and/or” should be construed in the same fashion, i.e., one or more of the elements so conjoined. Other elements may optionally be present other than the elements specifically identified by the “and/or” clause, whether related or unrelated to those elements specifically identified. Thus, as a non-limiting example, a reference to “A and/or B”, when used in conjunction with open-ended language such as “comprising” can refer, in one embodiment, to A only (optionally including elements other than B); in another embodiment, to B only (optionally including elements other than A); in yet another embodiment, to both A and B (optionally including other elements); etc. 
     As used herein in the specification and in the claims, “or” should be understood to have the same meaning as “and/or” as defined above. For example, when separating items in a list, “or” or “and/or” shall be interpreted as being inclusive, i.e., the inclusion of at least one, but also including more than one, of a number or list of elements, and, optionally, additional unlisted items. Only terms clearly indicated to the contrary, such as only one of or “exactly one of,” or, When used in the claims, “consisting of,” will refer to the inclusion of exactly one element of a number or list of elements. In general, the term “or” as used herein shall only be interpreted as indicating exclusive alternatives (i.e., “one or the other but not both”) when preceded by terms of exclusivity, such as “either,” “one of,” “only one of,” or “exactly one of.” 
     As used herein in the specification and in the claims, the phrase “at least one,” in reference to a list of one or more elements, should be understood to mean at least one element selected from anyone or more of the elements in the list of elements, but not necessarily including at least one of each and every element specifically listed within the list of elements and not excluding any combinations of elements in the list of elements. This definition also allows that elements may optionally he present other than the elements specifically identified within the list of elements to which the phrase “at least one” refers, whether related or unrelated to those elements specifically identified. Thus, as a nonlimiting example, “at least one of A and B” (or, equivalently, “at least one of A or B,” or, equivalently “at least one of A and/or B”) can refer, in one embodiment, to at least one, optionally including more than one, A, with no B present (and optionally including elements other than B); in another embodiment, to at least one, optionally including more than one, B, with no A present (and optionally including elements other than A); in yet another embodiment, to at least one, optionally including more than one, A, and at least one, optionally including more than one, B (and optionally including other elements); etc. 
     It should also be understood that, unless clearly indicated to the contrary, in any methods claimed herein that include more than one step or act, the order of the steps or acts of the method is not necessarily limited to the order in which the steps or acts of the method are recited. 
     In the claims, as well as in the specification above, all transitional phrases such as “comprising,” “including,” “carrying,” “having,” “containing,” “involving,” “holding,” “composed of,” and the like are to be understood to be open-ended, i.e., to mean including but not limited to. Only the transitional phrases “consisting of” and “consisting essentially of” shall be closed or semi-closed transitional phrases, respectively, as set forth in the 10 United States Patent Office Manual of Patent Examining Procedures, Section 2111.03. 
     With reference to  FIGS. 1 and 2 , side, partial and detailed cross-sectional views of an exemplary collapsible drill  100  (hereinafter “drill  100 ”) are provided. In particular, drill  100  is schematically illustrated in an extended and engaged position prior to complete penetration of a drilled material  102 , e.g., a wall, bone, cartilage, and the like. The drilled material  102  can define an outer surface  104 , e.g., the surface through which the drill  100  begins to drill, and an inner surface  106 , e.g., the surface at which, after penetration, it is desired to stop the drill  100  to prevent to prevent entrance of the drill  100  into an inner cavity  108 . The inner cavity  108  can include one or more structures (not shown) therein, e.g., blood vessels, nerves, electrical wires, and the like, and prevention of plunging into the inner cavity  108  with the drill  100  is desired to prevent damage to the one or more structures. 
     The exemplary drill  100  includes a chuck  110  configured and dimensioned to receive and/or retain a drill bit  112  therein. It should be understood that the chuck  110  can receive a variety of drill bit  112  sizes as needed by a user. In some embodiments, the chuck  110  can be a standard chuck utilized in the industry. In some embodiments, the drill bit  112  can be a standard drill bit utilized in the industry. The drill  100  further includes a piston  114  and a motor section  116 . The piston  114  includes a piston rod  118  and a cylinder  120  aligned along a central axis A. The piston rod  118  can define a distal end  122  and a proximal end  124 . In some embodiments, the piston rod  118  can define a solid structure, e.g., a non-hollow structure. The cylinder  120  can define a distal end  126  and a proximal end  128 . 
     The piston  114  can include a first pair of interlocking splines  130  and a second pair of interlocking splines  132 . The first pair of interlocking splines  130  can be located at the proximal end  128  of the cylinder  120  and can provide an interlocking or engagement interface between the motor section  116  and the cylinder  120  of the piston  114 . In some embodiments, the motor section  116  can include a plurality of grooves  134  radially spaced about the central axis A configured and dimensioned to interlock with a plurality of complementary teeth  136 , e.g., ridges, radially spaced about the central axis A of the outer surface of the proximal end  128  of the cylinder  120 . In some embodiments, the motor section  116  can include radially spaced teeth  136  and the proximal end  128  of the cylinder  120  can include radially spaced complementary grooves  134 . The first pair of interlocking splines  130  allows torque to be transferred from the motor section  116  to the piston  114  to regulate rotation of the piston  114 . For example, the motor section  116  can actuate or engage the grooves  134  to rotate about the central axis A which, in turn, actuate or engage the interlocked teeth  136  to rotate about the central axis A. Although not illustrated, those of ordinary skill in the art should understand that the motor section  116  includes a motor for creating the torque for rotating the grooves  134  of the first pair of interlocking splines  130 . 
     The second pair of interlocking splines  132  can be located at the distal end  126  of the cylinder  120  and a midpoint between the distal end  122  and the proximal end  124  of the piston rod  118 . The second pair of interlocking splines  132  can provide an interlocking or engagement interface between the piston rod  118  and the cylinder  118  of the piston  114 . In some embodiments, an inner surface of the distal end  126  of the cylinder  120  can include a plurality of grooves  138  radially spaced about the central axis A configured and dimensioned to interlock with a plurality of complementary teeth  140 , e.g., ridges, radially spaced about the central axis A of the outer surface of the piston rod  118 . In some embodiments, the cylinder  120  can include radially spaced teeth  140  and the piston rod  118  can include radially spaced complementary grooves  138 . The second pair of interlocking splines  132  allows torque coupling between the cylinder  118 , the piston rod  118  and the chuck  110  by engaging the teeth  140  with the grooves  138 . The torque from the motor section  116  can thereby be transferred to the chuck  110  to regulate rotation of the drill bit  112 . 
     In some embodiments, the distal end  122  of the piston rod  118  can be secured to the chuck  110  and the proximal end  124  can be movably engaged with the cylinder  120  of the piston  114 . In particular, the proximal end  124  of the piston rod  118  can he linearly translatable within the cylinder  120  along the central axis A. The cylinder  120  can include an inner radial ledge  142  located along the inner surface of the cylinder  120  at a midpoint between the distal end  126  and the proximal end  128  of the cylinder  120 . The ledge  142 , can extend from the inner surface of the cylinder  120  in the direction of the central axis A and can be configured to form a central aperture dimensioned to receive the piston rod  118  therethrough. The ledge  142  can act as a stop to limit translation of the piston rod  118  within the cylinder  120 . For example, the piston rod  118  can translate within the cylinder  120  along the central axis A until the teeth  140  of the second pair of interlocking splines  132  engage the ledge  142 . 
     The proximal end  124  of the piston rod  118  can include a radial protrusion  144  extended from the piston rod  118  and away from the central axis A. In particular, the proximal end  124  of the piston rod  118  can define a substantially flat surface extending across the entire diameter of the piston rod  118  and the radial protrusion  144  can further extend from the proximal end  124  surface away from the central axis A. The radial protrusion  144  can be configured and dimensioned to fit within the inner walls of the cylinder  120 . In some embodiments, the radial protrusion  144  can include an O-ring  146  secured thereon. The piston rod  118  can be assembled with the cylinder  120  such that the radial protrusion  144  is positioned between the ledge  142  and the proximal end  128  of the cylinder  120 . The piston rod  118  can thereby translate along the central axis A in the direction of the proximal end  128  of the cylinder  120  until the teeth  140  engage the ledge  142  and translate along the central axis A in the direction of the distal end  126  of the cylinder  120  until the radial protrusion  144  engages the ledge  142 . 
     Engagement of the radial protrusion  144  with the ledge  142  can form a seal between a first chamber  148  and the second chamber  150  of the cylinder  120 . The first chamber  148  can therefore be defined as the inner cavity of the cylinder  120  located between the proximal end  128  of the cylinder  120  and the radial protrusion  144  of the piston rod  118 . The second chamber  150  can be defined as the inner cavity of the cylinder  120  located between the ledge  142  and the distal end  126  of the cylinder  120 . In some embodiments, the drill  100  includes a sensor  152 , e.g., a force transducer, positioned between the motor section  116  and the proximal end  128  of the cylinder  120 . The sensor  152  can measure a reaction force from the drill bit  112  back to the motor section  116 . For example, the sensor  152  can measure the pressure imparted by the drill bit  112  against the drilled material  102  such that a change in the reaction force can be detected by the sensor  152  when the drill bit  112  has passed through the inner surface  106  of the drilled material  102 . 
     In some embodiments, the motor section  116  of the drill  100  can include a compressed air mechanism  154  therein. The compressed air mechanism  154  can include a compressor  156  with an inlet  158  and an outlet  160 . The compressed air mechanism  154  can further include a hose  162 , e.g., a flexible air hose, connecting the compressor  156  to the proximal end  128  of the cylinder  120 . The compressor  156  can intake compressed air through the inlet  158  and pass the compressed air through the hose  162  into the first chamber  148  of the cylinder  120 . The seal between the radial protrusion  144  and the ledge  142  can seal the first chamber  148  such that the compressed air can be maintained within the first chamber  148 . The compressor  156  can further release the compressed air from the first chamber  148  through the hose  162  and out of the outlet  160 . 
     Still with reference to  FIGS. 1 and 2 , when the drill  100  is positioned in an extended position for drilling, the piston rod  118  can be extended from the cylinder  120  such that the first and second pairs of interlocking splines  130 ,  132  are interlocked or engaged. In some embodiments, the piston rod  118  can be actuated into the extended position by filling or preloading the first chamber  148  with compressed air with the compressed air mechanism  154 . For example, the compressed air can impart a force on the proximal end  124  surface and the radial protrusion  144  surface of the piston rod  118  to linearly translate the piston rod  118  in the direction of the ledge  142  and seal the radial protrusion  144  against the ledge  142 . The compressed air area within the first chamber  148  can therefore impart and maintain a pressure against the radial protrusion  144  in the direction of the distal end  122  of the piston rod  118  to maintain the radial protrusion  144  and/or the O-ring  146  against the ledge  142 , thereby maintaining the compressed air pressure within the first chamber  148 . 
     Translation of the piston rod  118  into the extended position can interlock the grooves  138  and the teeth  140  of the second pair of interlocking splines  132 . The first pair of interlocking splines  130  can therefore provide torque transfer from the motor section  116  to the cylinder  120  and the second pair of interlocking splines  132  can provide torque transfer from the cylinder  120  to the piston rod  118 . The piston rod  118  can, in turn, provide torque to the chuck  110  and the drill bit  112 . 
     In some embodiments, the first and/or second pair of interlocking splines  130 ,  132  can allow a small movement between the piston  114  and the motor section  116  of the drill  100 . Based on the movement between the piston  114  and the motor section  116 , the sensor  152  positioned between the piston  114  and the motor section  116  can measure the reaction force from the drill bit  112  back to the motor section  116 . For example, when pressure is applied by the user performing the drilling in a linear and/or non-linear direction along the central axis A by pressing the tip  164  of the drill bit  112  and/or an area of the drill bit  112  adjacent to the tip  164  against the drilled material  102 , the pressure can be measured by the sensor  152 . As discussed above, the compressed air preloaded into the first chamber  148  with the compressed air mechanism  154  can maintain the piston  114  in the extended position. 
     During drilling, the pressure applied by the user against the drill bit  112  can vary. The compressed air mechanism  154  can therefore intake additional compressed air through the inlet  158  and into the first chamber  148  as needed to maintain or increase the compressed air pressure within the first chamber  148  of the piston  114  to resist the application of linear pressure and to maintain the piston  114  in the extended position. In some embodiments, the compressed air mechanism  154  can include a sensor (not shown) to detect the pressure within the first chamber  148 . Maintaining or increasing the pressure within the first chamber  148  of the piston  114  can maintain the interlock or engagement between the grooves  138  and the teeth  140  of the second pair of interlocking splines  132 . Torque can therefore be transferred from the motor section  116  to the piston  114 , the chuck  110  and the drill bit  112 . The drill bit  112  can thereby be rotated at the desired speed and can be advanced through the drilled material  102 . 
     Turning now to FIGS,  3  and  4 , side, partial and detailed cross-sectional views of an exemplary drill  100  are provided. In particular, the drill  100  is schematically illustrated in a collapsed and disengaged position after complete penetration of the drilled material  102 , e.g., a wall, bone, cartilage, and the like. As can be seen from  FIGS. 3 and 4 , the tip  164  of the drill bit  112  has fully passed through the drilled material  102 , including the inner surface  106  of the drilled material  102 . 
     During drilling, when the drill bit  112  penetrates the hard substance of the drilled material  102 , a sudden change in force or pressure occurs as imparted against the drill bit  112 . The change in force can be detected by the sensor  152  positioned between the piston  114  and the motor section  116 . Upon detection of the change in force imparted on the drill bit  112 , a solenoid valve (not shown) located in the compressor  156  can open to vent the compressed air in the first chamber  148  to atmosphere through the outlet  160 . The compressed air can thereby quickly exit from the piston  114 . 
     The decrease in pressure within the first chamber  148  simultaneously decreases the force imparted on the radial protrusion  144  of the piston rod  118  against the ledge  142  of the cylinder  120 , allowing translation of the piston rod  118  within the cylinder  120  along the central axis A. Thus, upon detection of the change in force imparted on the drill bit  112  and upon venting of the compressed air from the first chamber  148 , the chuck  110 , the drill bit  112  and the piston rod  118  can collapse or depress into the cylinder  120  of the piston  114  by translating along the central axis A until the teeth  140  of the piston rod  118  abut the ledge  142 . In some embodiments, the distance the piston rod  118  can collapse or depress into the cylinder  120  can be variable based on, e.g., the area desired by the user, the force applied by the user, the potential “plunge” distance expected, and the like. In some embodiments, the distance the piston rod  118  can collapse or depress into the cylinder  120  can be adjusted by the user and/or the manufacturer to range from a distance in millimeters to a distance in centimeters. 
     Continued pressure or force imparted by a user against a handle (not shown) of the drill  100  can cause the drill  100  to move forward without a force being imparted by the drill bit  112 . In particular, as the user continues to provide a force against the handle of the drill  100  to continue drilling, the chuck  110 , the drill bit  112  and the piston rod  118  can be forced to collapse or translate into the cylinder  120  of the piston  114  due to the vented first chamber  148 . Translation of the piston rod  118  along the central axis A in the direction of the ledge  142  due to the drop in pressure within the first chamber  148  forces the second pair of interlocking splines  132  between the piston rod  118  and the cylinder  120  to disengage. Disengagement of the second pair of interlocking splines  132  further releases the torque transfer from the cylinder  120  to the piston rod  118  and, in turn, the chuck  110  and the drill bit  112 . Rotation of the drill bit  112  can therefore be prevented. 
     In some embodiments, stopping rotation of the drill bit  112  can also stop further advancement of the drill bit  112  into the inner cavity  108  of the drilled material  102  by preventing the drill hit  112  from cutting away at the structure within the inner cavity  108 . In some embodiments, further advancement of the drill bit  112  into the inner cavity  108  of the drilled material  102  can be prevented by automatically and at least partially retracting the drill bit  112  out of the hole formed in the drilled material  102  when the piston rod  118  translates into the cylinder  120 . 
     The user can release or reduce the force applied to the handle of the drill  100  before the piston  114  completely collapses or depresses, e.g., before the teeth  140  of the piston rod  118  abut the ledge  142 , to prevent the stopped drill bit  112  from penetrating the soft matter, e.g., the nerves, blood vessels, and the like, within the inner cavity  108  beyond the hard substance of the drilled material  102  once the desired aperture has been formed. In terms of industrial uses, the user can release or reduce the force applied to the handle of the drill  100  before the piston  114  completely collapses to prevent the stopped drill bit  112  from penetrating the structures, e.g., the electrical wires, and the like, within the inner cavity  108  beyond the hard substance of the drilled material  102  once the desired aperture has been formed. 
     In some embodiments, the solenoid valve of the motor section  116  can open to a negative pressure reservoir (not shown). In some embodiments, the negative pressure reservoir can be generated electromechanically. Thus, when a drop in pressure is detected by the sensor  152 , the compressed air within the first chamber  148  can be actively decompressed, the first chamber  148  can be actively collapsed, and the piston rod  118  can be sucked into the cylinder  120  of the piston  114  until the teeth  140  of the piston rod  118  abut the ledge  142 . The chuck  110  and the drill bit  112  can thereby also be sucked in the direction of the cylinder  120  along the central axis A. Translation of the piston rod  118 , the chuck  110  and the drill bit  112  can prevent further advancement of the drill bit  112  into the inner cavity  108  of the drilled material  102 . In some embodiments, translation of the piston rod  118 , the chuck  110  and the drill bit  112  can actively and/or automatically retract the drill bit  112  away from the drilled material  102  and/or any structures within the inner cavity  108 . The force applied to the handle of the drill  100  can thereby be uncoupled from the force applied to the drill bit  112  to prevent damage to structures within the inner cavity  108  of the drilled material  112 . 
     If a user wishes to drill further through the same or another drilled material  102 , the first chamber  148  of the piston  114  can be refilled with compressed air through, e.g., actuation of a reset button, sensor detection, and the like. Although discussed herein as utilizing compressed air to fill the first chamber  148 , those of ordinary skill in the art should understand that any similar mechanism using a piston-like design with, e.g., one or more fluids, one or more springs, and the like, can be utilized for extending and/or collapsing the drill  100 . 
     While exemplary embodiments have been described herein, it is expressly noted that these embodiments should not be construed as limiting, but rather that additions and modifications to what is expressly described herein also are included within the scope of the invention. Moreover, it is to be understood that the features of the various embodiments described herein are not mutually exclusive and can exist in various combinations and permutations, even if such combinations or permutations are not made express herein, without departing from the spirit and scope of the invention.

Technology Category: a