Adjustable drill gauge

• US 4,710,075 A
• Filed: 10/01/1986
• Issued: 12/01/1987
• Est. Priority Date: 10/01/1986
• Status: Expired due to Term

• Current Assignee: DePuy Orthopaedics Incorporated (Johnson & Johnson)
• Original Assignee: Boehringer Mannheim Corporation
• Inventors: Davison, Dale
• Primary Examiner(s): Bilinsky, Z. R.
• Assistant Examiner(s): NOT, DEFINED
• Application Number:
  US06/914,079
• Time in Patent Office: 426 Days
• Field of Search: 408/202, 408/226, 408/241 S, 408/72 B, 408/115 B, 409/214, 409/218, 409/220, 33/169 B, 33/173, 33/201, 33/567
• US Class Current: 408/202
• CPC Class Codes: A61B 17/16 Bone cutting, breaking or removal means other than saws, e.g. Osteoclasts; Drills or chisels for bones; Trepans arthroscopic bone cutters A61B17/320016; dental implant drills potentially for other surgical use A61C8/0089; bone grinders A61F2/4644, A22C17/06; A61B17/1662 takes precedence over all other subgroups except A61B17/17
• CPC Class Codes: A61B 17/1668 for the upper femur A61B17/164 takes precedence
• CPC Class Codes: A61B 2090/033 Abutting means, stops, e.g. abutting on tissue or skin
• CPC Class Codes: B23B 2260/104 Markings, i.e. symbols or other indicating marks
• CPC Class Codes: B23B 49/005 Attached to the drill
• CPC Class Codes: B25F 5/003 Stops for limiting depth in rotary hand tools for drilling tools: B23B49/003
• CPC Class Codes: Y10T 408/8925 Depth-limiting member
• CPC Class Codes: Y10T 408/907 including detailed shank
• CPC Class Codes: Y10T 408/99 Adjustable stop

Abstract

A drill stop apparatus for use with an elongated drill bit is provided. The drill bit has a drilling end that is used to drill a hole of a specified, predetermined depth. The bit also has a plurality of circumferentially extending, axially spaced grooves formed on its outer surface. The drill stop includes a body having a first end and formed to include an axially extending bore that is sized to receive the drill bit to permit the bit to be moved axially within the body. The body also has a cavity that extends substantially perpendicularly through the bore. A plunger is provided that is sized to be received in the cavity for releasably engaging one of the plurality of grooves in the drill bit to lock the drill bit against axial movement within the body member such that a specified length of the drill bit extends beyond the first end of the body member. This specified length of the drill bit defines a specified operable drilling length between the first end of the stop apparatus and the drilling end of the drill bit.

Claims

1. A drill stop apparatus for use with an elongated drill bit having a drilling end used to drill a hole of a specified, predetermined depth, the drill bit having a plurality of circumferentially extending, axially spaced grooves formed thereon, the stop comprising,

a body member having a first end and formed to include an axially extending bore sized to receive said drill bit to permit said drill bit to be moved axially within said body member,

said body member also formed to include a cavity that extends substantially perpendicular through said bore, and

a plunger disposed in said cavity for releasably engaging one of said plurality of grooves in said drill bit to lock said drill bit against axial movement within said body member such that a specified length of said drill bit extends beyond said first end of said body member to define a specified operable drilling length of said drill bit between said first end and said drilling end, said plunger formed to include a transverse opening therethrough sized to receive said drill bit, said transverse opening including a ridge formed therein configured to engage selectively any one of said grooves in said drill bit to lock said drill bit against axial movement within said body member when said plunger is in a groove-engaging position, wherein a portion of said plunger extends beyond the outer surface of said body member, said extending portion adapted to be depressed by a force applied along an axis substantially perpendicular to the axis defined by said body member bore to move said plunger into a groove-disengaged position and spring means for yieldably urging said plunger into said groove-engaging position.

2. The apparatus of claim 1, wherein said body member includes a frustoconically-shaped portion that terminates at said first end.

3. A drill assembly for forming a hole of a specified depth in a bone for receiving a fracture-reducing implant, the assembly comprising,

a drill bit having an elongated shaft and a drilling end, the shaft including a plurality of circumferentially extending, axially spaced grooves formed thereon,

a stop member formed to include an axially extending bore sized to receive said shaft of said drill bit to permit said stop member to be moved axially along said shaft, and

a plunger configured to releasably engage one of said shaft grooves at a selected location along said shaft, the plunger being movable in said stop member along a plane substantially perpendicular to said shaft to releasably lock said stop member against movement along said shaft to define an operable portion of the drill bit between the stop member and the drilling end of the drill bit, the plunger being movable in response to a force applied along an axis that is substantially perpendicular to an axis defined by the stop member bore.

4. The assembly of claim 3, wherein said stop member is formed to include a cavity that extends substantially perpendicular to said stop member bore, and wherein said plunger is formed to include a hole extending therethrough and a ridge disposed in said hole, said plunger being sized to be received within said cavity such that said drill shaft extends through said hole and said ridge is sized and configured to selectively engage one of said shaft grooves to lock said stop member against movement with respect to said drill shaft.

5. The assembly of claim 4, wherein said plunger is movable between a groove-engaging position and a groove-disengaged position, and further comprising a spring to yieldably bias said plunger to the groove-engaging position.

6. The assembly of claim 5, further comprising a spring to yieldably bias said plunger to said groove-engaging position.

7. The assembly of claim 5, wherein said plunger operates along an axis that is generally perpendicular to the longitudinal axis of said drill bit.

8. A drill bit stop apparatus for use with a drill bit having an elongated shaft defining a first axis and having a cutting end and a plurality of circumferentially extending, axially spaced grooves formed thereon, the apparatus comprising,

a body member having a first end and configured to be slidably received for movement over said elongated shaft along said first axis, and

finger operated plunger means disposed within said body member for releasably engaging one of said plurality of said shaft grooves to lock said body member against movement along said first axis on said shaft while permitting rotational movement of the body member with respect to the shaft, said plunger means movable in response to a force applied along an axis substantially perpendicular to the first axis between a groove-engaging position and a groove-disengaging position, and

spring means for yieldably urging said plunger into the groove-engaging position.

9. The apparatus of claim 8, wherein said plunger means comprises a plunger member formed to include a passageway substantially aligned with said first axis and configured to receive said drill bit shaft and an upstanding ridge formed in said passageway, said ridge adapted to engage one of said plurality of shaft grooves when said plunger member is in a groove-engaging position.

10. An adjustable drill stop for use with an elongated drill having circumferentially extending, axially spaced grooves formed thereon, the stop comrprising,

a generally cylindrical housing formed to include a bore extending axially entirely through said housing, said housing also formed to include a cavity that extends into said housing through said aperture, said cavity oriented substantially perpendicular to said aperture,

a finger-operated plunger disposed in said cavity, said plunger formed to include an opening that is sized and oriented to receive a portion of said drill bit and including a ridge formed in said opening that is configured to releasably engage one of said grooves formed on said drill bit, said plunger movable from a groove-engaged position to a groove-disengaged position by application of a plunger-depressing force applied along an axis substantially perpendicular to an axis defined by said bore, and

a spring for releasably biasing said plunger to the groove-engaging position.