Surgical machine and method for operating a surgical machine

• US 20070147806A1
• Filed: 12/21/2006
• Published: 06/28/2007
• Est. Priority Date: 07/30/2004
• Status: Active Grant

• Current Assignee: Aesculap AG (B. Braun Holding GmbH & Co. KG)
• Original Assignee: Aesculap AG (B. Braun Holding GmbH & Co. KG)
• Inventors: Schneider, Juergen, Konrath, Harald, Hoegerle, Roland
• Granted Patent: US 7,400,107 B2
• Time in Patent Office: Days
• US Class Current: 388/827
• CPC Class Codes: A61B 17/1626 Control means; Display units
• CPC Class Codes: A61B 17/1628 Motors; Power supplies
• CPC Class Codes: A61B 17/32002 with continuously rotating, oscillating or reciprocating cutting instruments
• CPC Class Codes: A61B 2017/00017 Electrical control of surgical instruments

Abstract

To improve a surgical machine with an electric motor comprising a rotor and a plurality of motor windings, and with a motor controller for controlling and/or regulating the electric motor so that, in particular, the efficiency of the electric motor can be optimized essentially over the entire rotational speed range, it is proposed that the entire rotational speed range of the surgical machine be divided into at least one lower rotational speed range for low rotational speeds and at least one upper rotational speed range for higher rotational speeds than those in the at least one lower rotational speed range, that the motor controller be so designed that a first controlling and/or regulating method for controlling and/or regulating the electric motor is performable in the at least one lower rotational speed range, and that a second controlling and/or regulating method for controlling and/or regulating the electric motor is performable in the at least one upper rotational speed range.

Claims

1. Surgical machine with an electric motor comprising a rotor and at least two motor windings, and with a motor controller for controlling and/or regulating the electric motor, the entire rotational speed range of the surgical machine being divided into at least one lower rotational speed range for low rotational speeds and at least one upper rotational speed range for higher rotational speeds than those in the at least one lower rotational speed range, the motor controller being so designed that a first controlling and/or regulating method (A) for controlling and/or regulating the electric motor is performable in the at least one lower rotational speed range, and a second controlling and/or regulating method (B) for controlling and/or regulating the electric motor is performable in the at least one upper rotational speed range.

2. Machine in accordance with claim 1, wherein the first and/or the second controlling and/or regulating method (A, B) is a pulse width modulation (PWM) method.

3. Machine in accordance with claim 1, wherein the first controlling and/or regulating method (A) is a space vector pulse width modulation (SVPWM) method in which all motor windings are able to be simultaneously supplied with electric current.

4. Machine in accordance with claim 1, wherein the electric motor is a brushless DC motor.

5. Machine in accordance with claim 1, wherein the electric motor is a sensorless electric motor.

6. Machine in accordance with claim 1, wherein the electric motor comprises rotational speed detection sensors, and the motor controller is so designed that the first controlling and/or regulating method (A) is a method for controlling and/or regulating the surgical machine, in which the motor controller provides control signals for the electric motor in dependence upon an actual rotational speed determined with the rotational speed detection sensors.

7. Machine in accordance with claim 6, wherein a Hall system is provided for detecting an actual rotational speed of the electric motor, and the Hall system comprises the rotational speed detection sensors.

8. Machine in accordance with claim 1, wherein a rotational speed limit value (D_limit1, D_limit2) between the at least one lower rotational speed range and the at least one upper rotational speed range is unalterable.

9. Machine in accordance with claim 1, wherein a rotational speed limit value (D_limit1, D_limit2) between the at least one lower rotational speed range and the at least one upper rotational speed range is alterable.

10. Machine in accordance with claim 1, wherein the motor controller is so designed that a switchover from the first controlling and/or regulating method (A) to the second controlling and/or regulating method (B) takes place at a first switchover rotational speed (D_limit1), and a switchover from the second controlling and/or regulating method (B) to the first controlling and/or regulating method (A) takes place at a second switchover rotational speed (D_limit2).

11. Machine in accordance with claim 10, wherein the first switchover rotational speed (D_limit1) is equal to or greater than the second switchover rotational speed (D_limit2).

12. Machine in accordance with claim 1, wherein the motor controller is so designed that the switchover from the first controlling and/or regulating method (A) to the second controlling and/or regulating method (B) takes place automatically at the transition from the at least one lower rotational speed range to the at least one upper rotational speed range, and vice versa.

13. Machine in accordance with claim 1, wherein the electric motor comprises three motor windings.

14. Method for operating a surgical machine with an electric motor comprising a rotor and at least two motor windings, and with a motor controller for controlling and/or regulating the electric motor, wherein the entire rotational speed range of the surgical machine is divided into at least one lower rotational speed range for low rotational speeds and at least one upper rotational speed range for higher rotational speeds than those in the at least one lower rotational speed range, a first controlling and/or regulating method for controlling and/or regulating the electric motor is performed in the at least one lower rotational speed range, and a second controlling and/or regulating method for controlling and/or regulating the electric motor is performed in the at least one upper rotational speed range.

15. Method in accordance with claim 14, wherein the first and/or the second controlling and/or regulating methods are pulse width modulation (PWM) methods.

16. Method in accordance with claim 14, wherein the first controlling and/or regulating method is a space vector pulse width modulation (SVPWM) method, in which all motor windings are simultaneously supplied with electric current.

17. Method in accordance with claim 14, wherein an electric motor, which is a brushless DC motor, is used.

18. Method in accordance with claim 14, wherein an electric motor, which is a sensorless electric motor, is used.

19. Method in accordance with claim 14, wherein the motor comprises rotational speed detection sensors, and the first controlling and/or regulating method is a method for controlling and/or regulating the surgical machine, in which the motor controller provides control signals for the electric motor in dependence upon an actual rotational speed determined with the rotational speed detection sensors.

20. Method in accordance with claim 19, wherein a Hall system is provided for detecting an actual rotational speed of the electric motor, and the Hall system comprises the rotational speed detection sensors.

21. Method in accordance with claim 14, wherein a rotational speed limit value between the at least one lower rotational speed range and the at least one upper rotational speed range remains unaltered during operation of the machine.

22. Method in accordance with claim 14, wherein a rotational speed limit value between the at least one lower rotational speed range and the at least one upper rotational speed range is altered during operation of the machine.

23. Method in accordance with claim 14, wherein a switchover from the first controlling and/or regulating method to the second controlling and/or regulating method takes place at a first switchover rotational speed, and a switchover from the second controlling and/or regulating method to the first controlling and/or regulating method takes place at a second switchover rotational speed.

24. Method in accordance with claim 23, wherein the first switchover rotational speed is equal to or greater than the second switchover rotational speed.

25. Method in accordance with claim 14, wherein the switchover from the first controlling and/or regulating method to the second controlling and/or regulating method takes place automatically at the transition from the at least one lower rotational speed range to the at least one upper rotational speed range, and vice versa.

26. Method in accordance with claim 14, wherein an electric motor with three motor windings is used.