Mill head for a bone mill, the mill head having a floating cutting disc and an alignment feature for positioning the cutting disc so the disc will engage the drive spindle

Patent metadata

Field	Value
Publication number	US-10016204-B2
Application number	US-201715600275-A
Country	US
Kind code	B2
Filing date	May 19, 2017
Priority date	Nov 7, 2007
Publication date	Jul 10, 2018
Grant date	Jul 10, 2018

Abstract

A mill head for replaceable attachment to a base so as to collectively form a bone mill. The mill head includes shell with: a first opening in which bone stock is introduced into the head; and a second opening through which the bone chips are discharged. A cutting device is mounted in the shell to both rotate and move laterally. Attached to the cutting device are coupling features for engaging a drive spindle able to rotate the cutting device. Also attached to the housing is an alignment feature. The alignment feature engages a complementary alignment feature associated with the drive spindle so as a result of the engagement of the alignment features, the cutting device moves within the shell so that the cutting device coupling features are positioned to engage the drive spindle.

First claim

What is claimed is:

1. A bone mill for use with a base unit having a drive spindle, said bone mill including:
a housing having an inlet opening into which bone stock is introduced into said housing and an outlet opening spaced away from said inlet opening; and
a cutting device mounted in said housing between said inlet opening and said outlet opening, said cutting device being circular in shape so as to have a center and being mounted in said housing for rotation within said housing; and including:
at least one cutting edge that, when said cutting device is rotated, is configured to convert bone stock into bone chips;
at least one opening spaced radially outwardly from the center of said cutting device that is configured to engage a complementary tooth on the drive spindle of the base unit so that the rotation of the drive spindle results in the like rotation of said cutting device around the center of said cutting device; and
an alignment hole located at the center of said cutting device for engaging a base unit alignment pin of the drive spindle so that the engagement of said alignment results in the lateral positioning of said cutting device so that said tooth on the drive spindle can engage said opening on said cutting device and rotate said cutting device.

2. The bone mill of claim 1 , wherein said cutting device has 4 openings spaced radially outwardly from the center of said cutting device that are configured to engage 4 complementary teeth on the drive spindle of the base unit.

3. The bone mill of claim 1 , wherein said cutting device is disc shaped.

4. The bone mill of claim 1 , further including a tray removably attached to said housing adjacent said outlet opening for receiving bone chips discharged through said outlet opening.

5. The bone mill of claim 1 , wherein:
an impingement surface is disposed within said housing adjacent said inlet opening; and
said cutting device includes a disc on which said at least one cutting edge is formed, said at least one cutting edge being shaped and positioned relative to said impingement surface, as said cutting device rotates, said at least one cutting edge pushes bone stock against said impingement surface.

6. The bone mill of claim 5 , wherein: said disc is formed to have at least one opening, said opening at least being partially defined by said at least one cutting edge that pushes bone stock against said impingement surface and said cutting device is further mounted in said housing so that, as said cutting device rotates in the housing, first said opening and then said cutting edge that pushes bone stock against said impingement plate move towards said impingement surface.

7. A bone mill for use with a base unit having a drive spindle, said bone mill including:
a shell, said shell having: opposed and spaced apart top and bottom sections; a first opening in said shell top section; a second opening in said shell bottom section;
an exposed impingement surface integral with said shell top section;
a cutting disc seated in said shell between said impingement surface and said shell bottom section, said cutting disc having a planar shape and a center and being further formed to have at least one cutting member that is located above the plane of said cutting device that is configured to press bone stock introduced into said shell first opening against said impingement surface so that the bone stock is converted into bone chips for discharge through said shell second opening;
a structural member that extends downwardly from an inner surface of said shell top section that is directed towards said cutting disc so as to limit movement of said cutting disc, including said at least one cutting member, towards said shell top section and said impingement surface; and
a coupling assembly integral with said cutting device that includes plural equangularly spaced apart openings that are located outwardly of the center of said cutting disc that are shaped to receive said teeth of a spindle so that the rotation of said spindle results in a like rotation of said cutting disc.

8. The bone mill of claim 7 , wherein: said cutting disc is formed to have at least one opening, said opening at least being partially defined by the at least one cutting member that pushes bone stock against said impingement surface and said cutting device is further mounted in said housing so that, as said cutting device rotates in said housing, first said opening and then said cutting member that pushes bone stock against said impingement plate move towards said impingement surface.

9. The bone mill of claim 7 , wherein said at least one structural member of said housing that extends downwardly from an inner surface of said shell top section is ring shaped.

10. The bone mill of claim 7 , wherein said impingement surface is positioned to be adjacent said shell first opening.

11. The bone mill of claim 7 , wherein:
said shell is formed with a third opening in said shell bottom section, said third opening being separate from said first opening and said second opening; and
said coupling assembly is accessible through said third opening in said shell.

12. The bone mill of claim 7 , wherein said cutting disc is formed to have plural equangularly spaced apart openings that are centered around and spaced outwardly from the center of said disc, so that a section of said cutting disc that forms said openings functions as said coupling assembly.

13. The bone mill of claim 12 , wherein said cutting disc is further formed to have an opening in the center of said disc.

14. The bone mill of claim 7 , further including a tray removably attached to the bone mill adjacent said second opening for receiving bone chips discharged through said second opening.

15. The bone mill of claim 7 , further including a structural member extending upwardly from an inner surface of said bottom shell so as to space said cutting disc away from said inner surface of said bottom shell.

16. A bone mill for use with a base unit having a drive spindle, said bone mill including:
a housing having an inlet opening into which bone stock is introduced into said housing and an outlet opening spaced away from said inlet opening; and
a cutting device mounted in said housing between said inlet opening and said outlet opening, said cutting device being circular in shape so as to have a center and being mounted in said housing for rotation within said housing; and including:
at least one cutting edge that, when said cutting device is rotated, is configured to convert bone stock into bone chips;
at least one coupler spaced radially outwardly from said center of said cutting device that is configured to engage a complementary coupler on the drive spindle of said base so that said rotation of the drive spindle results in the like rotation of said cutting device around said center of said cutting device; and
an alignment coupler located at said center of said cutting device for engaging a base unit alignment coupler of the drive spindle so that said engagement of said alignment coupler located at said center of said cutting device and said alignment coupler of the drive spindle results in the lateral positioning of said cutting device so that said coupler on the drive spindle can engage said coupler on said cutting device and rotate said cutting device.

17. The bone mill of claim 16 , wherein:
said at least one coupler is at least one opening spaced radially outwardly from said center of said cutting device that is configured to engage a complementary tooth on the drive spindle of said base so that the rotati

Assignees

• Stryker Corp

Inventors

• Burmeister Richard
• Kalinka Gary
• Peterson Michael

Classifications

• A61F2/4644

  Preparation of bone graft, bone plugs or bone dowels, e.g. grinding or milling bone material (bone material A61F2/28; disintegrating or milling devices B02C) · CPC title

• A61B17/1615 Primary

  Drill bits, i.e. rotating tools extending from a handpiece to contact the worked material · CPC title

• B02C18/22

  Feed or discharge means · CPC title

• A61B2017/1602

  Mills · CPC title

• A61F2002/4645

  Devices for grinding or milling bone material · CPC title