Mechanism for can opener

1. A can opener mechanism for use in an opener for a can, said can comprising a cylindrical wall closed at each end with a circular lid fixed thereto by means of an upstanding rim around the edge of said lid that clamps onto said each end of said cylindrical wall, said mechanism comprising a body;

rotationally mounting to said body about a first axis, a drive wheel for engaging the rim of the can;

rotationally mounting to said body about a second axis and drivably rotatable by said drive wheel, a cutter wheel; eccentrically mounting to said cutter wheel, a cutting knife movable on rotation of the cutter wheel to a cutting position in which the cutting knife forms a nip, with its associated structures, with the drive wheel such that the cutting knife penetrates through the cylindrical wall of the can and to provide a cut therein as the opener orbits relatively therearound, wherein said cutting position is defined by a cutting interval corresponding to a segment of rotation of the cutter wheel in which the cutting knife is sufficiently proximal to the drive wheel to form said nip, with its associated structures, provided to the cutter wheel, intermittent drive means for providing intermittent drive between the drive wheel and the cutter wheel when the cutting knife is in the cutting position to maintain the nip, with its associated structures, in place for a sufficient cutting interval to provide a full orbital cut around the cylindrical wall of the can;

a mechanical sensor, associated with said mechanism, for sensing separation of the can with respect to the circular lid; and

a locking bar which locks said cutter wheel when said mechanical sensor is activated.

2. A can opener mechanism according to claim 1 , wherein the drive wheel and the cutter wheel are in a direct drive relationship.

3. A can opener mechanism according to claim 1 , wherein the cutting knife has circular form.

4. A can opener mechanism according to claim 1 , wherein the intermittent drive means comprises a Geneva mechanism.

5. A can opener mechanism according to claim 1 , wherein at the cutting position the usual drive relationship between the drive wheel and the cutter wheel is disengaged.

6. A can opener mechanism according to claim 5 , wherein the cutter wheel has missing teeth at the segment thereof.

7. A can opener mechanism according to claim 1 , wherein the cutter wheel turns in a forward and reverse cycle of less than three hundred sixty degrees.

8. A can opener mechanism according to claim 1 , wherein the cutter wheel turns in one direction only.

9. A can opener mechanism for use in an opener for a can, said can comprising a cylindrical wall closed at each end with a circular lid fixed thereto by means of an upstanding rim around the edge of said lid that clamps onto said each end of said cylindrical wall, said mechanism comprising a body;

rotationally mounting to said body about a first axis, a drive wheel for engaging the rim of the can;

rotationally mounting to said body about a second axis and drivably rotatable by said drive wheel, a cutter wheel; eccentrically mounting to said cutter wheel, a cutting knife movable on rotation of the cutter wheel to a cutting position in which the cutting knife forms a nip, with its associated structures, with the drive wheel such that the cutting knife penetrates through the cylindrical wall of the can and to provide a cut therein as the opener orbits relatively therearound, wherein said cutting position is defined by a cutting interval corresponding to a segment of rotation of the cutter wheel in which the cutting knife is sufficiently proximal to the drive wheel to form said nip, with its associated structures, provided to the cutter wheel, intermittent drive means for providing intermittent drive between the drive wheel and the cutter wheel when the cutting knife is in the cutting position to maintain the nip, with its associated structures, in place for a sufficient cutting interval to provide a full orbital cut around the cylindrical wall of the can, a sensor, associated with said mechanism, for sensing separation of the can with respect to the circular lid; and and wherein said intermittent drive means reverses to disengage upon sensed separation of the can.

10. A can opener mechanism according to claim 9 , wherein the sensor is a mechanical sensor.

11. A can opener mechanism according to claim 9 , wherein the sensor is an electronic sensor.

12. A can opener mechanism according to claim 9 , wherein the drive wheel and the cutter wheel are in a direct drive relationship.

13. A can opener mechanism according to claim 9 , wherein the cutting knife has circular form.

14. A can opener mechanism according to claim 9 , wherein the intermittent drive means comprises a Geneva mechanism.

15. A can opener mechanism according to claim 9 , wherein at the cutting position the usual drive relationship between the drive wheel and the cutter wheel is disengaged,

16. A can opener mechanism according to claim 15 , wherein the cutter wheel has missing teeth at the segment thereof.

17. A can opener mechanism according to claim 9 , wherein the cutter wheel turns in a forward and reverse cycle of less than three hundred sixty degrees.

18. A can opener mechanism according to claim 9 , wherein the cutter wheel turns in one direction only.