The present invention pertains to attachments for holding rotary tools and more particularly pertains to a tool driver suitable for use with an acetabular reamer cup or other similarly driven tool.
Acetabular reamer cups are surgical tools, which are used to cut hemispherical cavities in pelvis bones for the insertion of artificial hip joints. The acetabular reamer cups are mounted on tool drivers, which in turn are mounted in the chuck or collet of a portable drill or flexible powered shaft. Acetabular reamer cups are separable from their tool drivers for replacement purposes because it is difficult to sharpen or clean acetabular reamer cups. It may be necessary to change cups during an operation. Appropriate tool drivers are not inexpensive and must be reused.
Previous tool drivers usable with acetabular reamer cups grip the cup by means of a flange and slot and an opposed spring-loaded ball catch, like that on a socket wrench or socket driver. This presents a problem in that crack, crevices and intracately shaped parts tend to trap dried blood, which is very difficult to remove during cleaning. An additional problem is that unless tolerances of cups and tool drivers are made very close, at increased cost, there may be considerable free play between a cup and its tool driver. This increases wear and decreases the precision of the tool.
A tool driver for an acetabular reamer cup is subject to a number of restrictions. Due to the environment in which acetabular reamer cups are used, their interiors must be readily accessible for cleaning. This necessitates a large opening on the underside of each cup and eliminates methods of attaching the cup to a tool driver, which would block the underside. It is also best to minimize weight of the acetabular reamer, since surgeons must use it as a delicate instrument. This eliminates methods of attaching the cup to a tool driver, which tend to increase total tool weight. It is also best to eliminate interior angles of ninety degrees or less, within the cups to decrease contamination. This may require a cup which has a base that is convex rather than planar. Such a cup cannot be used with tool drivers that cannot tightly grip a curved surface. It is also best to minimize contamination, to have the acetabular reamer easily disassembleable into a small number of unitary parts for cleaning.
It is therefore highly desirable to provide an improved tool driver.
It is also highly desirable to provide an improved tool driver which can tightly grip and easily release an acetabular reamer cup.
It is also highly desirable to provide an improved tool driver, which does not have a large number of intricately shaped parts, cracks, crevices, or small angles.
It is also highly desirable to provide an improved tool driver which is lightweight and can tightly grip a tool having a base which is curved and surrounds a large opening.
It is also highly desirable to provide an improved tool driver which can be quickly and completely disassembled into a small number of pieces for cleaning.
It is finally highly desirable to provide an improved tool driver which meets all of the above desired features.