Patent ID: 12241502

DETAILED DESCRIPTION OF THE DISCLOSURE

Reference will now be made in detail to the various exemplary embodiments of the subject disclosure illustrated in the accompanying drawings. Wherever possible, the same or like reference numbers will be used throughout the drawings to refer to the same or like features. It should be noted that the drawings are in simplified form and are not drawn to precise scale. Certain terminology is used in the following description for convenience only and is not limiting. Directional terms such as top, bottom, left, right, above, below and diagonal, are used with respect to the accompanying drawings. The term “distal” shall mean away from the center of a body. The term “proximal” shall mean closer towards the center of a body and/or away from the “distal” end. The words “inwardly” and “outwardly” refer to directions toward and away from, respectively, the geometric center of the identified element and designated parts thereof. Such directional terms used in conjunction with the following description of the drawings should not be construed to limit the scope of the subject application in any manner not explicitly set forth. Additionally, the term “a,” as used in the specification, means “at least one.” The terminology includes the words above specifically mentioned, derivatives thereof, and words of similar import.

“About” as used herein when referring to a measurable value such as an amount, a temporal duration, and the like, is meant to encompass variations of ±20%, ±10%, ±5%, ±1%, or ±0.1% from the specified value, as such variations are appropriate.

“Substantially” as used herein shall mean considerable in extent, largely but not wholly that which is specified, or an appropriate variation therefrom as is acceptable within the field of art. “Exemplary” as used herein shall mean serving as an example.

Throughout the subject application, various aspects thereof can be presented in a range format. It should be understood that the description in range format is merely for convenience and brevity and should not be construed as an inflexible limitation on the scope of the subject disclosure. Accordingly, the description of a range should be considered to have specifically disclosed all the possible subranges as well as individual numerical values within that range. For example, description of a range such as from 1 to 6 should be considered to have specifically disclosed subranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6 etc., as well as individual numbers within that range, for example, 1, 2, 2.7, 3, 4, 5, 5.3, and 6. This applies regardless of the breadth of the range.

Furthermore, the described features, advantages and characteristics of the exemplary embodiments of the subject disclosure may be combined in any suitable manner in one or more embodiments. One skilled in the relevant art will recognize, in light of the description herein, that the subject disclosure can be practiced without one or more of the specific features or advantages of a particular exemplary embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all exemplary embodiments of the present disclosure.

Referring to the drawings,FIGS.1and2illustrate a tool drive assembly100in accordance with an exemplary embodiment of the present disclosure.FIG.2illustrates the tool drive assembly100connected to a working tool102. The working tool can be, e.g., a drill bit, a broken screw extractor or, as illustrated, a stripped screw extractor for extracting a stripped screw104from an unillustrated substrate. By way of example, but not limitation, screw104can be a bone screw and the unillustrated substrate can be bone.

The tool drive assembly100comprises a flexible drive shaft106and a guide108. The flexible drive shaft includes a proximal end110and a distal end112opposite the proximal end. The proximal end110of the flexible drive shaft106may be constructed, for example, as a Hudson connection or other suitable connection that is structured to engage a driver114such as a pneumatic drill, a hydraulic drill or a corded or cordless electric drill. The guide108comprises a handle116, a shaft118extending from the handle and a hub assembly120at a distal end122of the shaft.

FIGS.3A-3Dillustrate various features of the hub assembly120. The hub assembly120comprises a housing124and a hub126rotatably mounted within the housing. The housing includes a cylindrical housing portion128and the hub is mounted within the cylindrical housing portion. A longitudinal axis “A” of the cylindrical housing portion is coaxial with a longitudinal axis “B” of the hub.

The housing further includes a laterally extending mount130connected to the shaft118. The mount130includes a mounting face131having an angle of about 20 to 60 degrees including, e.g., 15, 25, 30, 35, 40, 45, 50, 55, 65, 70 and 75 degrees, relative to the longitudinal axis A of the cylindrical housing portion. The mount also includes a recess133for receiving a fastening tip of the shaft118. The recess is spaced from the distal end of the hub, e.g., above the socket counterbore or above the bearings136,136′. The shaft118may be releasably or fixedly connected to the mounted130. If releasably connected, the recess133can be configured to include threads or a detent to attach a correspondingly threaded or notched fastening tip of the shaft in the recess. If fixedly connected, the fastening tip of the shaft118can be welded in the recess. The shaft118is a rigid shaft which can be formed out of a metal or rigid polymer. That is, the rigid shaft can be a non-flexible shaft.

The hub126includes an input connection132structured to attach to or engage the distal end112of the flexible drive shaft106. The input connection extends upwardly or proximally along the direction of its longitudinal axis and has a proximally facing face135. According to an aspect, the input connection132is configured as a male connector. According to a further aspect, the input connection is structured to have a polygonal shaped longitudinal cross-section and may alternatively be configured, without limitation, to have the shape of a square male connector or other suitable shape. As best shown inFIG.3A, the input connection132includes a yieldable detent150, e.g., a ball-type detent, which is biased outwardly by a suitable biasing means152such as a spring or an elastomer to enable the input connection to releasably but firmly engage the distal end112of the flexible drive shaft106.

The hub further includes an output connection134structured to attach to or engage a working tool such as working tool102. According to an aspect, the output connection134is a female connector, e.g., a female socket. According to a further aspect, the output connection has a polygonal shaped longitudinal cross-section and may alternatively be configured, without limitation, to have the shape of a square female socket or any other suitable shape. The output connection has an opening facing downwardly or distally, opposite the proximally facing face135. A distal end of the output connection extends further than a most distal end of the cylindrical housing portion128. Further, the walls of the output connection are provided with a least one recess154configured to releasably yet firmly receive an unillustrated detent provided on the working tool102.

In addition to the foregoing, the hub assembly120further comprises a bearing136disposed between the hub126and the housing124to facilitate smooth rotation of the hub within the housing. The bearing136can be, e.g., an annular bearing, a bushing, a ball bearing and the like suitable for its intended purpose. The hub assembly can alternatively include more than one bearing e.g., a plurality of bearings136,136′.

FIGS.4-7illustrate various views of the flexible drive shaft106. According to an exemplary embodiment as shown inFIG.7, the flexible drive shaft comprises a series of alternating wound wires, e.g.,160,162,164,166surrounding a flexible mandrel168forming layers and covered by a flexible sleeve170. The flexible sleeve may be fabricated from any suitable flexible material including, without limitation, a polymer e.g., silicone, an elastomer, or a metal, e.g., corrugated tubing and the like.FIG.6shows the proximal end110of the flexible drive shaft bent at an angle of about 45 degrees with respect to the distal end112. The flexible drive shaft is structured sufficiently to allow bending or flexing between about 1 to 175 degrees, including 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, and 170 degrees, to provide the user optimum maneuverability when manipulating the flexible drive shaft. Depending on the length of the drive shaft which can range from about 2 to 24 or more inches, including 3, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22 and 25 inches, the drive shaft can be bent in an increasing degree of angle. For example, a very long shaft can be bent into a circle although such capability is not practical for most applications. An angle of 175 degrees is likely the maximum angle of bending but would be only needed in rare cases. More important is the effective radius of the bend. A shaft that can bend with a small radius typically compromises the torsional strength. Conversely, a shaft that can only bend with a large radius has exceptional torsional strength but compromises maneuverability. According to an exemplary embodiment, the flexible shaft is advantageously structured sufficiently to have a bend radius of about 1 inch to 6 inches, including 2, 3, 4 and 5 inches, and can withstand a torsional strength of about 50 to 400 inch-lbs. by optimizing the internal wire diameter, spacing between the wound internal wires, overall diameter, and wire material type used to form the flexible shaft. As used herein, a flexible shaft is defined as a shaft that is capable of bending without breaking or capable of being flexed.

As noted above, the proximal end110of the flexible drive shaft is structured to engage a driver such as driver114. The distal end112of the flexible drive is structured to connect to the input connection132of the hub126to rotatably drive the hub. According to an aspect, the distal end of the flexible drive shaft includes a female connector138such as, for example, a square socket.

Referring toFIGS.8A and8B, there are shown two exemplary embodiments of the guide108,108′ of the tool drive assembly according to the subject disclosure. As shown inFIG.8A, the shaft118extends from a central longitudinal axis “B” of the hub housing124at an angle “α1” of about 20 degrees. As shown inFIG.8B, the shaft118′ extends from a central longitudinal axis “B” of the hub housing124′ at an angle “α2” of about 60 degrees. It is understood that the angle of the shaft118with respect to the central longitudinal axis of the hub housing may be less than 20 degrees, between 20-60 degrees, and greater than 60 degrees including, e.g., 15, 25, 30, 35, 40, 45, 50, 55, 65, 70 and 75 degrees.

Referring toFIGS.8A and8B, according to an aspect, the tool drive assembly100according to the subject disclosure can comprise a kit including a guide assembly108,108′ comprising a handle having a guide shaft118, a first hub assembly including a first housing124having a substantially cylindrical housing portion and a laterally extending mount130connectable to the guide shaft118at a first angle α1relative to a central longitudinal axis of the first housing. The first hub assembly further includes a first hub126mounted within the first housing124, the first hub having a first input connection132structured to engage the distal end of the flexible guide shaft118, and a first output connection134structured to engage a working tool102. The guide assembly108,108′ further comprises a second hub assembly including a second housing124having a substantially cylindrical housing portion and a laterally extending mount130connectable to the guide shaft118at a second angle α2relative to a central longitudinal axis of the second housing, wherein the second angle is greater than the first angle. The second hub assembly further includes a second hub126mounted within the second housing124, the second hub126having a second input connection132structured to engage the distal end of the flexible guide shaft118, and a second output connection134structured to engage the working tool102. Each of the laterally extending mounts130of the first and second housings124,124include a recess or connection for releasably connecting to a distal end of the guide shaft118.

Prior to operation, a user selects an appropriate guide108, attaches the proximal end110of the flexible drive shaft106to the driver114, attaches the distal end112of the flexible drive shaft to the input connection132of the hub126, and attaches the working tool102to the output connection134of the hub. The user then grasps the handle116and moves the distal end of the guide to the region or object to be worked by the working tool. By way of example, but not limitation, the working tool can be a stripped screw extractor which is inserted into the stripped head of a screw to be extracted. While holding the guide in position, the user activates the driver114to rotate the flexible drive shaft106, the hub126and the working tool102until the distal end of the working tool becomes embedded in the stripped head of the screw. The user then operates the driver to extract the screw from the substrate. Owing to the flexibility of the flexible drive shaft and the maneuverability of the guide, the user can comfortably move the tool drive assembly100to effectively operate the working tool to achieve a variety of ends including, without limitation, hole drilling, stripped screw extraction and broken screw extraction.

It will be appreciated by those skilled in the art that changes could be made to the exemplary embodiments described above without departing from the broad inventive concept thereof. It is to be understood, therefore, that this disclosure is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the subject disclosure as defined by the appended claims.