WO2008100253A1

WO2008100253A1 - Improved drill apparatus

Info

Publication number: WO2008100253A1
Application number: PCT/US2007/003833
Authority: WO
Inventors: Fathali Ghahremani; Jamshi Ghajar
Original assignee: Neurodynamics Inc
Current assignee: Neurodynamics Inc
Priority date: 2007-02-12
Filing date: 2007-02-12
Publication date: 2008-08-21
Anticipated expiration: 2009-08-12

Abstract

A drill having clips to control the depth of penetration of the drill bit is provided in which the clips are moveable and are integrally connected to the drill so as not to be separated from the drill when removed from the path of movement of the drill bit assembly. A planetary gear is coupled between a rotate able knob and the drill bit to more effectively, control speed and vertical movement of the drill bit. The drill is especially suited to cranium drilling procedures because of the fineness of movement and effective limits on amount of movement as well as controlling the movement to be perpendicular to the surface being penetrated. However because of the high degree of control other professionals and artisans can also use it as well.

Description

TITLE: IMPROVED DRILL APPARATUS BACKGROUND OF THE INVENTION

This invention relates to an apparatus and a method for an improved manual drill, including such a drill especially adapted for safely drilling an orifice in a human cranium more accurately and more safely than currently available with other drills. The invention includes a means for passing a catheter into the cranium in a trajectory that assure correct medical placement.

The inventors herein are also inventors in US Patent 4,931,056 entitled Catheter Guide Apparatus for Perpendicular Insertion Into a Cranium, which patent issued on June 5, 1990 and shows a manual drill operated by a manually operated knob which is rotated and moves the drill bit into the cranium.

Over the years, the inventors have continued to work on this project and have evolved certain improvements. One improvement is illustrated in US Patent 6,206,885 entitled Catheter Guide and Drill Apparatus and Method for Perpendicular Insertion Into a Cranium Orifice, in which a plurality of clips are associated with the motion of the drill bit, limiting the motion to that permitted by the stop clip. As each stop clip is removed, the drill bit can move further into the cranium, but the clips prevent unwanted penetration of the drill bit.

In the prior cranium drill apparatus illustrated in the '885 patent, as each clip is removed from blocking the path of the drill bit, it is set-aside during the surgery. As is well understood, the efficacy of surgery is related, in part, to accounting for all loose items used in the operating room. The small plastic clips associated with the controlled movement cranium drill are light and easily dropped or misplaced, thus sometimes necessitating a search and locate operation in order to account for all individual items used in the surgical room.

Additionally, even if a non-medical consumer uses this improved drill, it is problematic to have removable clips because of the ease with which they are lost. As the knob of the drill is manually rotated moving the drill bit, it penetrates further into the object being drilled, such as the cranium. The rotation of the knob is directly coupled to the depth of penetration of the drill bit, and extremely fine drill bit movement may be difficult to achieve with prior art apparatus.

An object of this invention is to provide an improved drill in which the penetration of the drill bit is blocked and limited beyond that safely controlled, yet the blocking mechanism is maintained integral with the drill bit apparatus.

Another object of this invention is to provide such an adjustable stop mechanism, which is easily moved from the path of movement of the drill bit without interfering with the drilling procedure.

A still further object of this invention is to provide a cranium drill in which the movement of the knob controlling the depth of movement of the drill bit permits finer vertical control than that presently available.

Another object of the mechanism is to provide a means for controlling the direction of the ventricular catheter during the therapeutic insertion of this mechanism into the brain.

Yet another object of this invention is to provide a planetary gear system such that the rotation of the manual knob is coupled through such planetary gear to the drill bit to increase its speed and improve the amount of vertical movement of the drill bit in relation to the rotation of the manual knob. Furthermore, the planetary gear system increases the rotational speed of the bit improving the drill penetration of the surface.

Still another object of this invention is to provide a lightweight and easily handled drill, which can be conveniently used for medical and nonmedical purposes.

Other objects, advantages and features of this invention will become more apparent from the following description.

SUMMARY OF THE INVENTION

In accordance with the principles of this invention, the above objects are accomplished by providing a manual drill having a drill bit moving substantially perpendicular to the control knob and to the surface of the cranium to be drilled. A rod substantially parallel to the drill bit carries a plurality of moveable clips one on top of the other which are hingedly connected to the rod but moveable out of the path of the movement of the mechanism advancing the drill bit. Maintaining the clips fixedly attached yet hingedly moveable out of the path of movement of the drill bit allows the clips to be sequentially removed from the path of movement yet be attached to the drill so that after a procedure is completed, the clips are always present and attached to the body of the drill.

In accordance with another feature of this invention, a planetary gear system is employed between the manually rotated knob and the drill bit allowing for a three or four or five to one ratio so as to more effectively control the drilling speed and depth of penetration of the drill bit. Currently, there is a direct non-planetary coupling system in which the movement of the knob is carried directly to the movement of the drill bit, and the ability to perform finer drill bit movement is unavailable. The planetary gear assembly of the present o invention is entirely carried in the undersurface of the manual knob so as to enable a user to use the drill in the standard fashion without having to alter his/her method of use. A finer drill bit advance is realized and more control during the surgical procedure is affected.

Further gradations depicting the depth of movement of the drill are provided, and the drill bits can be interchanged for changing drill bit sizes.

Once the drilling and full penetration of the cranium is achieved, a lumen restrictor is applied to the guidance mechanism to allow accurate and directed motion of the catheter into the brain.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a perspective of the drill of this invention showing the major components of the drill assembly. Some major components are shown in cross section to allow better visualization of the inter-relation of the components:

Fig. 2 is a perspective drawing showing the drill and guidance device fully assembled as well as showing that various drill bits could be assembled onto the drill. -A-

Fig. 3 is a perspective of the drill of this invention showing two of the clips removed from blocking downward penetration of the drill bit:

Fig. 4a and 4b are perspectives of the guide base used in Figure 1 showing the use of the Insert (Catheter Guide) for the medical user.

DETAILED DESCRIPTION

Fig.1 is a perspective exploded view of the drill showing all the components of the drill. A list of components is provided as follows:

1. 10-Drive Components a. 11 -Drill Bit b. 12-Drive Shaft c. 13-Drill Bit Lock Screw d. 14-Spacer e. 15-Spacer Lock f. 16-Center Drive Spur Gear g. 17-ldIer Spur Gears h. 18-Drive Spur Gears i. 19-Drill shaft j. 20-Drive Handle k. 21 -Outer Gear Drive I. 22-Drive Handle Bottom

2. 30-Shaft/Gear Holder Housing: a. 31-Upper Gear Holder b. 32-Spur Gear Shafts c. 33-Connecting Rod Guide Holes d. 34-Spur Gear Holding Surface e. 35-Lower Gear Holder f. 36-Connecting Rod Lock Shaft g. 37-Spacer Lock Surface h. 38-Depth Indicator Mark

3. 40-Clip Assembly: a. 41 -Lower Clip b. 42-Lower Clip Handle c. 43-First Intermediary Clip d. 44-First Intermediary Clip Handle e. 45-Second Intermediary Clip f. 46-Second Intermediary Clip Handle g. 47-Upper Clip h. 48-Upper Clip Handle i. 49-Clip Hinge Connecting Rod j. 50-Clip Holding Connecting Rod

4. 60-Guide Base a. 61 -Drive Shaft Guide Hole b. 62-Guide Base Legs c. 63-Shaft/Gear Holder Housing Guide d. 64-Shaft Gear Holder Housing Case e. 65-Spacer/lnsert Lock Hole f. 66-Depth Mark Face g. 67-Depth Marking h. 68-HoId Down Grips

5. 70-lnsert (Catheter Guide) a. 71-lnsert Lock b. 72-Catheter Guide Hole c. 73-Catheter Removal Slot

Many parts such as drive handle 20, drive handle bottom 22, upper gear holder 31 , lower gear holder 35 are shown in cross section. Fig. 1 also is a perspective view of the drill, which shows a planetary gear system composed of outer gear drive 21 (that can be integral to drive handle 20) which drives the drive spur gears 18 which through idler spur gears 17 drive the center drive spur gear 16. The drive spur gears 18 and idler spur gears 16 are free to rotate on spur gear shafts 32 that are integral to upper gear holder 31. The relative position of all the spur gears are maintained by the spur gear holding surface 34 of the upper gear holder 31. The center spur gear 16 is connected to the drive shaft 12 either by molding, hard connection with a screw or other means of fixation. The planetary gear system is held together by the drive handle bottom 22 that locks the upper gear holder 31 to the drive handle 20 while allowing the drive handle 20 to rotate freely relative to the upper gear holder 31.

A traditional drive handle 20 as shown in any of Figs. 1-3 is seated on top of the shaft to closely and snugly fit with the assembly therebelow. As is clear from Fig. 1 , the planetary gear system (composed of outer gear 21 , drive spur gears 18, idler spur gears 17 and center drive spur gear 16) translates the rotary movement of the drive handle 20 (with integral outer gear drive 21) through a drive shaft 12 that is integrally connected with drill bit 11 causing the drill bit 11 to rotate as determined by the movement of the drive handle 20. More or fewer planetary gears could be employed to provide the desired level of smoothness of operation.

By housing the planetary gear system entirety within and under the drive handle 20; a user will achieve greater control of movement without altering the conventional manner in which the user has used prior drills. This enhances the likely acceptance of the invention and otherwise improves the efficiency, operation and accuracy of the drilling operation.

Fig. 2 shows the drill 100 of this invention having a manually rotated drive handle, 20, suitable to bear against the palm of the hand of a user or be controlled by fingers only, a generally vertical shaft section 30 with a guide base 60 of a generally rectangular configuration flaring from the bottom of the shaft and having bottom legs 62 which sit perpendicularly on the object being drilled and a drill bit 11 projecting downwardly there from to accomplish the drilling function. In describing this invention reference is concurrently made to Fig. 1 because of the detail shown therein as well as the related parts list given above. The drive handle 20 and the shaft/gear holder housing are locked to the guide base 60 with the spacer lock 15 arms that fit into spacer/insert lock hole 65. Thus as seen in Fig.2, the whole drive assembly drive handle 20, shaft/gear holder housing 30, clip assembly 40 and drill bit 11 can move up or down relative to guide base 60 in fixed increments as determined by the movement of individual clips (41 , 43, 45, 47) and penetration of the surface by the drill bit. As the handle or knob 20 of Fig. 2 is rotated, that motion is coupled to down-wardly or upwardly move drill bit 11 with the proper orientation of the drill bit 11 being maintained perpendicular by the legs 62 of guide base 60 set on the object being drilled.

One of the objects of this invention is to ensure that the penetration of the drill bit is safely controlled by providing clips 41 , 43, 45, 47 that sit upon spacer 14. This spacer 14 is locked to guide base 60 by spacer lock 15 on surface 37 and engages the clips on the top surface preventing undesired downward or forward movement of the drill bit beyond each clip.

As particularly shown in Fig 2, drill bit 11 may be of different sizes. By releasing the drill bit lock screw 13 a drill bit 11 can be removed from drive shaft 12. The drill shaft 19 of a different drill bit 11 can then be inserted into the drive shaft 12 and locked into place by drill bit lock screw 13 allowing the user to choose the size of drill needed for a particular operation.

Referring more particularly to Fig. 3, there is shown the upper surface of spacer 14, and two clips 41 and 43 moved out of blocking positions. The second intermediary clip 45 is shown in the blocking position, and the lower edge of clip 45 bears on upper surface of spacer 14 blocking the drill bit 11 from further vertical downward movement. As each clip is sequentially hingedly rotated out of a blocking position, the drill bit can advance that additional distance until the next clip is removed from the blocking position. As shown in Fig. 3, the depth of penetration can be carefully controlled by moving the clips in a sequential manner from the lower clip 41 to the upper clip 47, and errors are more likely to be avoided.

An aspect of the present invention is to provide a structure whereby the clips 41. 43, 45, 47 are easily moved out of the path of movement of the shaft by pressing on the clip handles 42, 44, 46, 48 to remove them from the clip holding connecting rod 50 and moving them out of the path of the spacer 14. These clips 40 are hinged on the shaft/gear housing 30 with clip hinge connecting rod 49 and are integral with and cannot be physically removed from the drill bit apparatus. As described above, in surgical procedures it is necessary to account for all items in the surgical theater. Previously, the clip approach to control the depth of movement of the drill bit comprised an apparatus in which the clips were physically separated from the drill apparatus, thereby requiring a search of such clips after the surgical procedure was completed.

Referring to Fig 3 gradations 67, such as index lines are vertically carried on a depth mark face 66 of a housing 64 surrounding the drill 11. The shaft/gear holder housing 30 moves along the edge 66, and the alignment of the depth indicator mark 38 with the gradations 67 provide an indication of the depth of penetration.

The clips are integral with shaft/gear holder housing 30 and when moved out of their blocking positions, the clips are still attached to unit 30 through clip hinge connecting rod 50. When a drilling or surgical procedure is completed, all clips are easily accounted for because they were not separated from the drill assembly.

Once the drilling operation is completed, the drill assembly (drive handle 20, shaft/gear holder housing 30, clip assembly 40) can be unsnapped from the guide base 60. The shaft of insert 70 is placed into drive shaft hole 61 and the insert lock 71 is pressed into spacer/insert lock hole until it snaps into place. The ventricular catheter is passed through the catheter guide hole 72 until the desired depth as determined by the physician is achieved. The assembly of guide base 60 and insert 70 is removed from the catheter through catheter removal slot 73.

While this drill invention has been described with reference to cranial drilling, the drill may be more widely used, such as in the home by homeowners by artisans and by professionals. The clips provide a unique safety to prevent undesired drilling errors, and by maintaining the clips attached to the drill, one cannot easily lose the safety clips. Additionally, by designing the planetary gears to sit within the knob or handle, one can easily move the drill bit by pressing one's palm against the handle and rotating the handle. The fabrication of the drill can be of lightweight materials such as plastics further reducing its weight and facilitating widespread use.

It should be understood that the preferred embodiment was described to provide the best illustration of the principles of the invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly legally and equitably entitled.

Claims

CLAIMS:

1. A drill comprising: a rotate able handle suitable to bear against the palm of a person's hand, the rotation of which is coupled to provide movement of a drill bit, mechanical clips located between the handle and drill bit to physically block movement of said drill bit, said clips comprising a plurality of clips located one on top of the other and hingedly attached to a rod passing through said clips, said clips attached to said drill, said clips selectively hingedly moveable out of the path of movement of said drill bit.

2. A drill as set forth in claim 1 , wherein said clips are permanently attached to said drill.

3. A drill as set forth in claim 1 or 2 further comprising a shaft located between said handle and said drill bit, a clip assembly unit attached to said shaft and including said clips integrally formed with said unit, a guide base located below said unit for guiding said drill bit, said guide base having an upper horizontal surface, said horizontal surface of said guide base interacting with said clips, whereby said horizontal surface prevents movement of said drill bit when a selected clip is positioned to block such movement.

4. A drill as set forth in claim 3, wherein said clips comprise a number of clips (typically four clips) aligned with each other.

5. A drill as set forth in claims 1 or 2, further comprising a blocking surface integrally formed with said drill located between said handle and drill bit, said clips interacting with said blocking surface to prevent movement of said drill bit.

6. A drill as set forth in claim 5, wherein said clip comprises four individual clips aligned with each other.

7. A drill as set forth in claim 1 or 2, further comprising a planetary gear system interposed between said rotate able knob and said drill bit to control the movement of said drill bit.

8. A drill comprising a drill bit and a rotate able knob, the rotation of which is coupled to move said drill bit, further comprising a planetary gear system located in a housing under said knob, whereby rotation of said knob is coupled to said drill bit through said planetary gear system.

9. A drill according to claim 8, wherein said planetary gear system is hidden from view underneath said knob.

10. A drill according to claims 1-3, further comprising a plurality of gradations associated with movement of said drill bit to provide a visual indication of the amount of movement of said drill bit.

11. A drill according to claim 1 , 2 or 8 wherein said drill bit is interchangeable with different sized drill bits.