DE102011050101B4 - Surgical motor control and/or regulation device, surgical drive system and method for controlling and/or regulating a surgical drive unit - Google Patents

Abstract

Surgical motor control and/or regulation device (12) for controlling and/or regulating a surgical drive unit (14) with a sensorless electric motor (68), which has a motor housing (144), a rotor (142) and at least two motor windings (72a, 72b, 72c), which motor control and/or regulation device (12) is designed to control and/or regulate the drive unit (14) by means of a method for controlling and/or regulating the drive unit (14), characterized by a motor stopping device (140) to stop the electric motor (68) down to a speed of zero revolutions per unit of time in such a way that the rotor (142) assumes a defined rotational position relative to the motor housing (144), which defines a rest position, and- a standby mode in which the electric motor (68) with a speed requirement of zero revolutions per time unit after a rest period trest, in which the at least two motor windings (72a, 72b, 72c) are not energized, is energized for as long as defined to rotate the rotor (142) of the electric motor (68 ) automatically, i.e. without a speed request, after at least one full revolution to return to the rest position.

Description

The present invention relates to a surgical motor control and/or regulation device for controlling and/or regulating a surgical drive unit with a sensorless electric motor, which comprises a motor housing, a rotor and at least two motor windings, which motor control and/or regulation device is designed for Controlling and/or regulating the drive unit by means of a method for controlling and/or regulating the drive unit.

Furthermore, the present invention includes a method for controlling and/or regulating a surgical drive unit with a sensorless electric motor, which includes a motor housing, a rotor and at least two motor windings.

Furthermore, the present invention relates to a surgical drive system comprising at least one control and/or regulation device and at least one surgical drive unit that can be connected and controlled with it and/or at least one surgical instrument comprising a surgical drive unit, wherein the at least one drive unit comprises a sensorless electric motor with a Rotor and at least two motor windings, the control and/or regulation device being designed to control and/or regulate the drive unit by means of a method for controlling and/or regulating the drive unit.

A surgical motor control and/or regulation device for controlling and/or regulating a surgical drive unit is known, for example, from DE 10 2009 018 143 A1 known. She is trained to control and/or regulate sensorless motors, in particular electronically commutated DC motors. In this context, sensorless means that no speed sensor is provided on the motor in order to determine its speed. In the case of sensorless electric motors, this is usually determined by determining the back EMF (electromotive force), i.e. by determining the induced voltage in a motor winding that is not energized.

Without a speed sensor, however, the rotor position of the sensorless electric motor cannot be determined directly either. Rather, this requires at least one revolution of the rotor. However, since the position, i.e. the rotational position of the rotor relative to the motor housing, is not known, it is possible that the motor does not start up in the requested direction of rotation at the beginning.

From the DE 100 60 634 A1 a jacket-loadable drum type washing machine is known.

It is therefore an object of the present invention to improve a surgical motor control and/or regulation device as well as a method and a surgical drive system of the type described above such that the electric motor always starts up immediately from standstill with the desired direction of rotation.

• - eine Motoranhalteeinrichtung zum Anhalten des Elektromotors bis auf eine Drehzahl von Null Umdrehungen pro Zeiteinheit derart, dass der Rotor eine definierte Drehstellung relativ zum Motorgehäuse einnimmt, welche eine Ruhestellung definiert, und
• - einen Bereitschaftsmodus, in welchem der Elektromotor bei einer Drehzahlanforderung von Null Umdrehungen pro Zeiteinheit nach einer Ruhezeit t_Ruhe, in welcher die mindestens zwei Motorwicklungen unbestromt sind, so lange definiert bestromt wird, um den Rotor des Elektromotors automatisch, nämlich ohne Drehzahlanforderung, nach mindestens einer vollen Umdrehung wieder in die Ruhestellung zu überführen.

This object is achieved according to the invention in a surgical motor control and/or regulation device of the type described above in that it is characterized by

• - A motor stopping device for stopping the electric motor down to a speed of zero revolutions per unit time in such a way that the rotor assumes a defined rotational position relative to the motor housing, which defines a rest position, and
• - A stand-by mode in which the electric motor is energized at a speed requirement of zero revolutions per time unit after a rest period t _rest , in which the at least two motor windings are not energized, for as long as defined to automatically, namely without a speed requirement, after at least one full turn back to the rest position.

Providing the proposed motor stopping device makes it possible to bring the rotor of the electric motor into a defined rotational position relative to the motor housing, namely into the rest position. Knowing this position then makes it possible, in particular, to energize the stationary and unenergized electric motor in such a way that it can immediately be set in rotation with the desired direction of rotation. The electric motor is therefore ready for use more quickly and does not have to be braked again and then restarted with the opposite direction of rotation if it turns in the wrong direction when starting. It is also advantageous that the motor control and/or regulation device includes a standby mode in which the electric motor is energized for a defined period of time after a rest period t rest at a speed requirement of zero revolutions per unit of _time in order to restart the rotor after at least one full revolution to transfer to the rest position. For example, the rotor of the electric motor can be cyclically brought into the rest position again and again. Compared to a permanent current supply in the hold mode, the motor is not heated as much. Nevertheless, even after a tool change, it is in a defined position Position to enable the motor to start safely and in a defined manner from a standstill.

The starting of the electric motor can be further improved in particular if the motor control and/or regulation device includes a direction of rotation request memory for storing the last direction of rotation request before braking the electric motor to the speed of zero revolutions per unit time. If, in addition to the rest position of the rotor, the last direction of rotation request is known, the electric motor can be started up even more reliably with the desired direction of rotation.

Preferably, the surgical motor control and/or regulation device comprises a home position memory for storing the home position of the rotor. In particular, the rest position can always be the same rotational position of the rotor relative to the motor housing. However, it can also be a different rotational position of the rotor relative to the motor housing each time. In particular, by providing a rest position memory, it is possible to simply store only that position or rotational position of the rotor that it assumes immediately after it has come to a standstill.

It can be favorable if the motor stopping device is designed in such a way that it always stops the rotor in the same rest position. Such a motor stopping device makes it possible to always bring the rotor into the same rotational position, which then defines the rest position. Providing only a single rest position has the advantage that the electric motor can always be started up in a specific direction of rotation in the same way.

It is favorable if the engine control and/or regulation device includes a holding mode in which the rotor is actively held in the rest position. Providing such a mode has the particular advantage that accidental rotation of the rotor, for example when changing the surgical processing tool that can be coupled to the surgical drive, can be avoided. The motor control and/or regulation device can, for example, keep the rotor in the rest position by means of a corresponding energization. One can also say that the rotor is parked in the rest position, so that the rest position defines a quasi-parking position of the rotor. For example, a mechanical holding or braking device can be provided, which engages or comes into engagement with the rotor in the holding mode in order to hold it in the rest position.

The rotor can be held in the rest position in a particularly simple manner if the motor control and/or regulation device comprises a hold mode energizing device for energizing the electric motor in the hold mode in order to actively hold the rotor in the rest position without rotating it. With the hold mode energizing device, the electric motor can be energized in particular in such a way that an increased torque is required in order to twist it out of the rest position, which can happen unintentionally when changing tools, for example.

It is advantageous if the motor control and/or regulation device includes a holding time specification device for specifying a holding time t _hold during which the electric motor is continuously energized in order to hold the rotor in the rest position without rotating it. The holding time specification device has the particular advantage that the electric motor only has to be energized for the holding time t _hold in order to hold it in the rest position. In this way, the energy requirement for holding the rotor in the rest position, ie for parking it, can be minimized, as can motor heating as a result of the energization. The holding time specification device can in particular be designed in such a way that an operator can set the holding time or that the holding time is permanently specified at the factory, for example.

It is favorable if a holding time presetting device can preset a holding time t _stop of a maximum of 20 minutes. Typically, pauses in the operation of a surgical drive, for example during a surgical intervention, are shorter than 20 minutes, so that the electric motor does not have to be energized for an excessively long time when it is stationary.

According to a further preferred embodiment of the invention, a motor current limiting device can be provided for limiting a motor current in order to actively keep the rotor in the rest position, without turning it, to a maximum of 20% of the nominal value of the electric motor. The motor current limiting device preferably limits a motor current to a maximum of 10% of the rated value of the electric motor. With such a motor current limiting device, the motor heating can be kept as small as possible, so that it is practically unnoticeable. Since heating is proportional to the square of the current flowing, reducing the current flowing to 10%, for example, can limit heating to just 1%.

It is advantageous if the motor control and/or regulation device is designed in such a way that in the standby mode the rotor is repeatedly brought back into the rest position. So it is possible in particular to bring the rotor back into the rest position or its parking position cyclically, that is to say regularly or also irregularly. In other words, this can be done as long as the engine control and/or regulation device is in the standby mode.

The engine control and/or regulation device preferably includes a speed limitation device for limiting a maximum speed of the rotor in the standby mode. In particular, the maximum speed of the rotor in standby mode can be limited to a maximum of 5 revolutions per minute. In this way it can be ensured that the rotor turns or rotates only very slowly when it is brought back into the rest position or back into the rest position again in the standby mode despite a speed request of zero revolutions per unit of time. In particular, it can be avoided that someone can be injured on a tool coupled to the drive while the rotor is being moved into the rest position.

It is favorable if the engine control and/or regulation device includes a standby time specification device for specifying a standby time t _standby of the standby mode. For example, as explained above in connection with the hold mode, the stand-by time t stand _-by can also be specified, during which the motor control and/or regulation device is in the stand-by mode.

A standby time t _standby of a maximum of 20 minutes can preferably be specified with the standby time specification device. With such a standby time specification, it is possible to keep a surgical drive, insofar as it is required for a surgical intervention, on standby in such a way that the rotational position of the rotor, i.e. its rest position or parking position, is very likely to be known at the time a speed request is made to the electric motor is.

It is favorable if the engine control and/or regulation device includes a switching device for switching at least once after the standby time t _{standby has} expired from the standby mode to the hold mode. This makes it possible, for example, to switch automatically from standby mode to hold mode.

It is advantageous if the switching device is designed to switch at least once after the hold time t _hold has elapsed from the hold mode to the standby mode. For example, it is possible to automatically switch from the hold mode to the standby mode after the hold time has expired. For example, the hold time can be 5 minutes and the standby time can be 15 minutes. This means that when the electric motor is at a standstill, it is initially actively held in the parking position for 5 minutes by applying the appropriate current and then, for example, the rotor can be cyclically returned to the parking position in standby mode.

The object set at the outset is also achieved according to the invention in a method of the type described at the outset in that when the electric motor is braked down to a speed of zero revolutions per unit of time, the electric motor is stopped in such a way that the rotor assumes a defined rotational position relative to the motor housing, which Defined rest position, and that in a standby mode of the electric motor with a speed requirement of zero revolutions per time unit after a rest period t _rest , in which the at least two motor windings are not energized, the electric motor is energized for a defined period of time to turn the rotor of the electric motor automatically, namely without Speed request to return to the rest position after at least one full revolution.

In particular, this method makes it possible to bring the electric motor into a defined rest position. The rotor then assumes a quasi-parking position. From there, it can then simply and safely be rotated again, immediately in the desired direction.

So that the motor can easily and reliably start up with the desired direction of rotation, it is advantageous if the last direction of rotation request before the electric motor is braked to the speed of zero revolutions per unit of time is stored. In this way, the position of the rotor is known so that it can be energized immediately in the desired way in order to start up in the correct direction of rotation.

Preferably, the rest position of the rotor is stored. If this is known, the electric motor can be energized simply and safely in order to rotate it in the desired manner.

In order to make control of the electric motor as simple as possible, it is advantageous if the rotor always assumes the same rotational position relative to the motor housing in the rest position. This also means that in particular it automatically always assumes the same rotational position relative to the stator of the electric motor.

In order to avoid that the rotor goes into an undefi ned position, for example when changing instruments or tools, it is advantageous if the rotor is actively held in the rest position in a holding mode of the electric motor. For example, this can be achieved by braking the rotor shaft, in particular mechanically and/or electrically.

The electric motor is preferably energized in the holding mode in order to actively hold the rotor in the rest position without rotating it. For example, this can be achieved by energizing a single winding of the electric motor, so that the rotor can align itself in a position relative to the housing or to the stator and can thus assume a defined rest position or parking position.

It is advantageous if the electric motor is constantly supplied with current during a holding time t _hold in order to hold the rotor in the rest position without rotating it. In this way it can be ensured that the rotor remains in the rest position during the hold time and that its position is known when the next speed request is made.

The hold time t _hold is preferably a maximum of 20 minutes. In this way, excessive heating of the motor can be avoided and energy consumption can be minimized.

To further minimize an energy requirement in the holding mode, it is advantageous if a motor current, in order to actively hold the rotor in the rest position without twisting it, is no more than 20% of the nominal value of the electric motor. It is preferably not more than 10%. In this way, heating of the motor can be minimized and it can still be ensured that a torque required for twisting the rotor from the rest position is sufficiently large to prevent accidental rotational movement, for example when changing tools.

It is favorable if, in a standby mode of the electric motor with a speed requirement of zero revolutions per time unit, after a rest period t _rest , the electric motor is energized for a defined period of time in order to bring the rotor back into the rest position after at least one full revolution. In other words, the rotor of the electric motor is automatically moved into the rest position, namely without a speed requirement.

In the standby mode, the rotor is preferably repeatedly brought back into the rest position. This means that after a certain time the motor is energized again in order to bring the rotor back into the defined rest position. This can be the stored rest position or a new rest position. The repeated transfer of the rotor into the rest position can take place cyclically, at regular intervals or also irregularly.

In order to avoid the risk of injury to people and objects, it is advantageous if a maximum speed in standby mode is no more than 5 revolutions of the rotor per minute. Such a low speed is practically difficult for an operator to perceive and makes it possible to bring the rotor into the rest position almost unnoticed.

The electric motor favorably assumes the standby mode for a standby time t _standby . In this way it can be avoided that the electric motor is kept in standby mode for an excessively long time, that is to say significantly longer than necessary.

The standby time t _standby is preferably a maximum of 20 minutes. After the stand-by time has elapsed, the electric motor can simply stand still without a speed request.

After the stand-by time t stand-by has elapsed, the electric motor preferably switches from the stand-by _mode to the hold mode at least once. This variant makes it possible to combine the advantages of standby mode and hold mode.

It can also be advantageous if the electric motor changes from the hold mode to the standby mode at least once after the hold time t _hold has expired. This variant is favorable because the electric motor can be actively held in the rest position for the holding time t _Halt . Only after the end of the holding time t _Halt can it be switched to the standby mode, in which, with a minimum energy requirement and thus also a minimum heating of the electric motor, the rotor is still very likely to assume a defined parked position or rest position if there is a speed requirement again enters

The object stated at the outset is also achieved according to the invention in a surgical drive system of the type described at the outset in that the control and/or regulation device is designed in the form of one of the motor control and/or regulation devices described above. The surgical drive system then also has the advantages described above in connection with preferred embodiments of motor control and/or regulation devices. A control and/or regulation device with an engine stopping device makes it possible to bring the rotor of the electric motor into a defined position, namely the rest position, in order to enable the electric motor to start up from the rest position in a simple and safe manner. In particular, starting of the electric motor counter to the desired direction of rotation can be avoided in this way.

Furthermore, it is favorable if the control and/or regulation device is designed to control and/or regulate the drive unit by means of a method for controlling and/or regulating the drive unit as described above. The drive system then also has the advantages described above in connection with preferred variants of the method.

1. 1. Chirurgische Motorsteuerungs- und/oder -regelungsvorrichtung (12) zum Steuern und/oder Regeln einer chirurgischen Antriebseinheit (14) mit einem sensorlosen Elektromotor (68), welcher ein Motorgehäuse (144), einen Rotor (142) und mindestens zwei Motorwicklungen (72a, 72b, 72c) umfasst, welche Motorsteuerungs- und/oder -regelungsvorrichtung (12) ausgebildet ist zum Steuern und/oder Regeln der Antriebseinheit (14) mittels eines Verfahrens zum Steuern und/oder Regeln der Antriebseinheit (14), gekennzeichnet durch eine Motoranhalteeinrichtung (140) zum Anhalten des Elektromotors (68) bis auf eine Drehzahl von Null Umdrehungen pro Zeiteinheit derart, dass der Rotor (142) eine Drehstellung relativ zum Motorgehäuse (144) einnimmt, welche eine Ruhestellung definiert.
2. 2. Chirurgische Motorsteuerungs- und/oder -regelungsvorrichtung nach Satz 1, gekennzeichnet durch einen Drehrichtungsanforderungsspeicher (154) zum Speichern der letzten Drehrichtungsanforderung vor dem Abbremsen des Elektromotors (68) auf die Drehzahl von Null Umdrehungen pro Zeiteinheit.
3. 3. Chirurgische Motorsteuerungs- und/oder -regelungsvorrichtung nach Satz 1 oder 2, gekennzeichnet durch einen Ruhestellungsspeicher (156) zum Speichern der Ruhestellung des Rotors (142).
4. 4. Chirurgische Motorsteuerungs- und/oder -regelungsvorrichtung nach einem der voranstehenden Sätze, dadurch gekennzeichnet, dass die Motoranhalteeinrichtung (140) derart ausgebildet ist, dass sie den Rotor (142) immer in derselben Ruhestellung anhält.
5. 5. Chirurgische Motorsteuerungs- und/oder -regelungsvorrichtung nach einem der voranstehenden Sätze, gekennzeichnet durch einen Haltemodus, in welchem der Rotor (142) aktiv in der Ruhestellung gehalten wird.
6. 6. Chirurgische Motorsteuerungs- und/oder -regelungsvorrichtung nach Satz 5, gekennzeichnet durch eine Haltemodusbestromungseinrichtung (160) zum Bestromen des Elektromotors (68) im Haltemodus, um den Rotor (142), ohne ihn zu verdrehen, aktiv in der Ruhestellung zu halten.
7. 7. Chirurgische Motorsteuerungs- und/oder -regelungsvorrichtung nach Satz 5 oder 6, gekennzeichnet durch eine Haltezeitvorgabeeinrichtung (162) zum Vorgeben einer Haltezeit t_Halt, während der der Elektromotor (68) ständig bestromt wird, um den Rotor (142), ohne ihn zu verdrehen, in der Ruhestellung zu halten.
8. 8. Chirurgische Motorsteuerungs- und/oder -regelungsvorrichtung nach Satz 7, dadurch gekennzeichnet, dass mit der Haltezeitvorgabeeinrichtung (162) eine Haltezeit t_Halt von maximal 20 Minuten vorgebbar ist.
9. 9. Chirurgische Motorsteuerungs- und/oder -regelungsvorrichtung nach einem der Sätze 5 bis 8, gekennzeichnet durch eine Motorstrombegrenzungseinrichtung (166) zum Begrenzen eines Motorstroms, um den Rotor (142), ohne ihn zu verdrehen, aktiv in der Ruhestellung zu halten, auf maximal 20 % des Nennwertes des Elektromotors (68).
10. 10. Chirurgische Motorsteuerungs- und/oder -regelungsvorrichtung nach einem der voranstehenden Sätze, gekennzeichnet durch einen Bereitschaftsmodus, in welchem der Elektromotor (68) bei einer Drehzahlanforderung von Null Umdrehungen pro Zeiteinheit nach einer Ruhezeit t-_Ruhe so lange definiert bestromt wird, um den Rotor (142) nach mindestens einer vollen Umdrehung wieder in die Ruhestellung zu überführen.
11. 11. Chirurgische Motorsteuerungs- und/oder -regelungsvorrichtung nach Satz 10, dadurch gekennzeichnet, dass sie derart ausgebildet ist, dass im Bereitschaftsmodus der Rotor (142) immer wieder neu in die Ruhestellung überführt wird.
12. 12. Chirurgische Motorsteuerungs- und/oder -regelungsvorrichtung nach Satz 10 oder 11, gekennzeichnet durch eine Drehzahlbegrenzungseinrichtung (168) zum Begrenzen einer Maximaldrehzahl des Rotors (142) im Bereitschaftsmodus auf maximal 5 Umdrehungen pro Minute.
13. 13. Chirurgische Motorsteuerungs- und/oder -regelungsvorrichtung nach einem der Sätze 10 bis 12, gekennzeichnet durch eine Bereitschaftszeitvorgabeeinrichtung (170) zum Vorgeben einer Bereitschaftszeit t_Bereitschaft des Bereitschaftsmodus.
14. 14. Chirurgische Motorsteuerungs- und/oder -regelungsvorrichtung nach Satz 13, dadurch gekennzeichnet, dass mit der Bereitschaftszeitvorgabeeinrichtung (170) eine Bereitschaftszeit t_Bereitschaft von maximal 20 Minuten vorgebbar ist.
15. 15. Chirurgische Motorsteuerungs- und/oder -regelungsvorrichtung nach einem der Sätze 10 bis 14, gekennzeichnet durch eine Umschalteinrichtung (174) zum mindestens einmaligen Umschalten nach Ablauf der Bereitschaftszeit t_Bereitschaft vom Bereitschaftsmodus in den Haltemodus.
16. 16. Chirurgische Motorsteuerungs- und/oder -regelungsvorrichtung nach Satz 15, dadurch gekennzeichnet, dass die Umschalteinrichtung (174) ausgebildet ist zum mindestens einmaligen Umschalten nach Ablauf der Haltezeit t_Halt vom Haltemodus in den Bereitschaftsmodus.
17. 17. Verfahren zum Steuern und/oder Regeln einer chirurgischen Antriebseinheit (14) mit einem sensorlosen Elektromotor (68), welcher ein Motorgehäuse (144), einen Rotor (142) und mindestens zwei Motorwicklungen (72a, 72b, 72c) umfasst, dadurch gekennzeichnet, dass beim Abbremsen des Elektromotors (68) bis auf eine Drehzahl von Null Umdrehungen pro Zeiteinheit der Elektromotor (68) derart angehalten wird, dass der Rotor (142) eine Drehstellung relativ zum Motorgehäuse (144) einnimmt, welche eine Ruhestellung definiert.
18. 18. Verfahren nach Satz 17, dadurch gekennzeichnet, dass die letzte Drehrichtungsanforderung vor dem Abbremsen des Elektromotors (68) auf die Drehzahl von Null Umdrehungen pro Zeiteinheit gespeichert wird.
19. 19. Verfahren nach Satz 17 oder 18, dadurch gekennzeichnet, dass die Ruhestellung des Rotors (142) gespeichert wird.
20. 20. Verfahren nach einem der Sätze 17 bis 19, dadurch gekennzeichnet, dass der Rotor (142) in der Ruhestellung immer dieselbe Drehstellung relativ zum Motorgehäuse (144) einnimmt.
21. 21. Verfahren nach einem der Sätze 17 bis 20, dadurch gekennzeichnet, dass in einem Haltemodus des Elektromotors (68) der Rotor (142) aktiv in der Ruhestellung gehalten wird.
22. 22. Verfahren nach Satz 21, dadurch gekennzeichnet, dass der Elektromotor (68) im Haltemodus bestromt wird, um den Rotor (142), ohne ihn zu verdrehen, aktiv in der Ruhestellung zu halten.
23. 23. Verfahren nach Satz 21 oder 22, dadurch gekennzeichnet, dass der Elektromotor (68) während einer Haltezeit t_Halt ständig bestromt wird, um den Rotor (142), ohne ihn zu verdrehen, in der Ruhestellung zu halten.
24. 24. Verfahren nach Satz 23, dadurch gekennzeichnet, dass die Haltezeit t_Halt maximal 20 Minuten beträgt.
25. 25. Verfahren nach einem der Sätze 21 bis 24, dadurch gekennzeichnet, dass ein Motorstrom, um den Rotor (142), ohne ihn zu verdrehen, aktiv in der Ruhestellung zu halten, nicht mehr als 20 % des Nennwertes des Elektromotors (68) beträgt.
26. 26. Verfahren nach einem der Sätze 17 bis 25, dadurch gekennzeichnet, dass in einem Bereitschaftsmodus des Elektromotors (68) bei einer Drehzahlanforderung von Null Umdrehungen pro Zeiteinheit nach einer Ruhezeit t_Ruhe der Elektromotor (68) so lange definiert bestromt wird, um den Rotor (142) nach mindestens einer vollen Umdrehung wieder in die Ruhestellung zu überführen.
27. 27. Verfahren nach Satz 26, dadurch gekennzeichnet, dass im Bereitschaftsmodus der Rotor (142) immer wieder neu in die Ruhestellung überführt wird.
28. 28. Verfahren nach Satz 26 oder 27, dadurch gekennzeichnet, dass eine Maximaldrehzahl im Bereitschaftsmodus nicht mehr als 5 Umdrehungen des Rotors (142) pro Minute beträgt.
29. 29. Verfahren nach einem der Sätze 26 bis 29, dadurch gekennzeichnet, dass der Elektromotor (68) für eine Bereitschaftszeit t_Bereitschaft den Bereitschaftsmodus einnimmt.
30. 30. Verfahren nach Satz 29, dadurch gekennzeichnet, dass die Bereitschaftszeit t_Bereitschaft maximal 20 Minuten beträgt.
31. 31. Verfahren nach Satz 29 oder 30, dadurch gekennzeichnet, dass der Elektromotor (68) nach Ablauf der Bereitschaftszeit t_Bereitschaft vom Bereitschaftsmodus mindestens einmal in den Haltmodus wechselt.
32. 32. Verfahren nach einem der Sätze 26 bis 31, dadurch gekennzeichnet, dass der Elektromotor (68) nach Ablauf der Haltezeit t_Halt vom Haltemodus mindestens einmal in den Bereitschaftsmodus wechselt.
33. 33. Chirurgisches Antriebssystem umfassend mindestens eine Steuer- und/ oder Regelungsvorrichtung (12) und mindestens eine mit dieser verbindbare und ansteuerbare chirurgische Antriebseinheit (14) und/oder mindestens ein eine chirurgische Antriebseinheit (14) umfassendes chirurgisches Instrument (176), wobei die mindestens eine Antriebseinheit (14) einen sensorlosen Elektromotor (68) mit einem Rotor (142) und mindestens zwei Motorwicklungen (72a, 72b, 72c) umfasst, wobei die Steuer- und/oder Regelungsvorrichtung (12) ausgebildet ist zum Steuern und/ oder Regeln der Antriebseinheit (14) mittels eines Verfahrens zum Steuern und/oder Regeln der Antriebseinheit (14), gekennzeichnet durch eine Motoranhalteeinrichtung (140), welche das Anhalten des Elektromotors (68) bis auf eine Drehzahl von Null Umdrehungen pro Zeiteinheit derart steuert, dass der Rotor (142) eine Drehstellung relativ zum Motorgehäuse (144) einnimmt, welche eine Ruhestellung definiert.
34. 34. Chirurgisches Antriebssystem nach Satz 33, dadurch gekennzeichnet, dass die Steuer- und/oder Regelungsvorrichtung (12) in Form einer Motorsteuerungs- und/oder -regelungsvorrichtung (12) nach einem der Sätze 1 bis 16 ausgebildet ist.
35. 35. Chirurgisches Antriebssystem nach Satz 33 oder 34, dadurch gekennzeichnet, dass die Steuer- und/oder Regelungsvorrichtung (12) ausgebildet ist zum Steuern und/oder Regeln der Antriebseinheit (14) mittels eines Verfahrens zum Steuern und/oder Regeln der Antriebseinheit (14) nach einem der Sätze 17 bis 32.

The above description thus includes in particular the embodiments of a surgical motor control and/or regulation device, a surgical drive system and a method for controlling and/or regulating a surgical drive unit defined in the following numbered sentences:

1. 1. Surgical motor control and/or regulation device (12) for controlling and/or regulating a surgical drive unit (14) with a sensorless electric motor (68), which has a motor housing (144), a rotor (142) and at least two motor windings ( 72a, 72b, 72c), which engine control and/or regulation device (12) is designed to control and/or regulate the drive unit (14) by means of a method for controlling and/or regulating the drive unit (14), characterized by a Motor stopping device (140) for stopping the electric motor (68) down to a speed of zero revolutions per unit time such that the rotor (142) assumes a rotational position relative to the motor housing (144) which defines a rest position.
2. 2. Surgical motor control and/or regulation device according to sentence 1, characterized by a direction of rotation request memory (154) for storing the last direction of rotation request before braking the electric motor (68) to the speed of zero revolutions per unit time.
3. 3. Surgical motor control and/or regulation device according to sentence 1 or 2, characterized by a home position memory (156) for storing the home position of the rotor (142).
4. 4. Surgical motor control and/or regulation device according to one of the preceding sentences, characterized in that the motor stopping device (140) is designed in such a way that it always stops the rotor (142) in the same rest position.
5. 5. Surgical motor control and/or regulation device according to any one of the preceding sentences, characterized by a hold mode in which the rotor (142) is actively held in the rest position.
6. 6. Surgical motor control and/or regulation device according to sentence 5, characterized by a holding mode energizing device (160) for energizing the electric motor (68) in the holding mode in order to actively hold the rotor (142) in the rest position without twisting it.
7. 7. Surgical motor control and/or regulation device according to sentence 5 or 6, characterized by a holding time specification device (162) for specifying a holding time t _halt , during which the electric motor (68) is constantly energized to turn the rotor (142) without it to twist, to hold in the rest position.
8. 8. Surgical motor control and/or regulation device according to sentence 7, characterized in that a holding time t _hold of a maximum of 20 minutes can be preset with the holding time presetting device (162).
9. 9. Surgical motor control and/or regulation device according to one of sentences 5 to 8, characterized by motor current limiting means (166) for limiting a motor current in order to actively keep the rotor (142) in the rest position without twisting it maximum 20% of the rated value of the electric motor (68).
10. 10. Surgical motor control and/or regulation device according to one of the preceding sentences, characterized by a stand-by mode in which the electric motor (68) is energized at a speed requirement of zero revolutions per unit of time after a rest period t-rest for a defined period of _time to Rotor (142) to be brought back into the rest position after at least one full revolution.
11. 11. Surgical motor control and/or regulation device according to sentence 10, characterized in that it is designed in such a way that in the standby mode the rotor (142) is repeatedly transferred to the rest position.
12. 12. Surgical motor control and/or regulation device according to sentence 10 or 11, characterized by a speed limiting device (168) for limiting a maximum speed of the rotor (142) in ready shaft mode to a maximum of 5 revolutions per minute.
13. 13. Surgical motor control and/or regulation device according to one of sentences 10 to 12, characterized by a standby time specification device (170) for specifying a standby time t _standby of the standby mode.
14. 14. Surgical motor control and/or regulation device according to sentence 13, characterized in that a standby time t _standby of a maximum of 20 minutes can be specified with the standby time specification device (170).
15. 15. Surgical motor control and/or regulation device according to one of sentences 10 to 14, characterized by a switching device (174) for switching at least once after the standby time t _standby has expired from the standby mode to the hold mode.
16. 16. Surgical motor control and/or regulation device according to sentence 15, characterized in that the switching device (174) is designed to switch at least once after the holding time t _hold has expired from the holding mode to the standby mode.
17. 17. Method for controlling and/or regulating a surgical drive unit (14) with a sensorless electric motor (68) which comprises a motor housing (144), a rotor (142) and at least two motor windings (72a, 72b, 72c), characterized that when the electric motor (68) is braked down to a speed of zero revolutions per unit of time, the electric motor (68) is stopped in such a way that the rotor (142) assumes a rotational position relative to the motor housing (144) which defines a rest position.
18. 18. The method according to sentence 17, characterized in that the last request for the direction of rotation before the electric motor (68) is braked to the speed of zero revolutions per unit time is stored.
19. 19. The method according to sentence 17 or 18, characterized in that the rest position of the rotor (142) is stored.
20. 20. The method according to any one of sentences 17 to 19, characterized in that the rotor (142) in the rest position always occupies the same rotational position relative to the motor housing (144).
21. 21. The method according to any one of sentences 17 to 20, characterized in that in a holding mode of the electric motor (68), the rotor (142) is actively held in the rest position.
22. 22. The method according to sentence 21, characterized in that the electric motor (68) is energized in the holding mode in order to actively hold the rotor (142) in the rest position without twisting it.
23. 23. The method according to sentence 21 or 22, characterized in that the electric motor (68) is continuously energized during a holding time t _stop in order to keep the rotor (142) in the rest position without rotating it.
24. 24. The method according to sentence 23, characterized in that the hold time t _hold is a maximum of 20 minutes.
25. 25. The method according to any one of sentences 21 to 24, characterized in that a motor current in order to actively keep the rotor (142) in the rest position without twisting it is not more than 20% of the nominal value of the electric motor (68). .
26. 26. The method according to any one of sentences 17 to 25, characterized in that in a standby mode of the electric motor (68) with a speed requirement of zero revolutions per time unit after a rest period t rest, the electric motor (68) is energized for a defined period of _time to rotate the rotor (142) to return to the rest position after at least one full revolution.
27. 27. The method according to sentence 26, characterized in that in the standby mode the rotor (142) is repeatedly transferred to the rest position.
28. 28. The method according to sentence 26 or 27, characterized in that a maximum speed in the standby mode is no more than 5 revolutions of the rotor (142) per minute.
29. 29. The method according to any one of sentences 26 to 29, characterized in that the electric motor (68) assumes the standby mode for a standby time t _standby .
30. 30. The method according to sentence 29, characterized in that the standby time t _standby is a maximum of 20 minutes.
31. 31. The method according to sentence 29 or 30, characterized in that the electric motor (68) changes from the standby mode to the hold mode at least once after the standby _time t standby has expired.
32. 32. The method according to any one of sentences 26 to 31, characterized in that the electric motor (68) changes from the holding mode to the standby mode at least once after the holding _time t hold has elapsed.
33. 33. Surgical drive system comprising at least one control and/or regulation device (12) and at least one surgical drive unit (14) that can be connected and controlled with it and/or at least one surgical instrument (176) comprising a surgical drive unit (14), wherein the at least a drive unit (14) comprises a sensorless electric motor (68) with a rotor (142) and at least two motor windings (72a, 72b, 72c), wherein the control and/or regulating device (12) is designed to control and/or regulate the Drive unit (14) by means of a method for controlling and/or regulating the drive unit (14), characterized by a motor stopping device (140) which controls the stopping of the electric motor (68) down to a speed of zero revolutions per unit of time in such a way that the rotor (142) assumes a rotational position relative to the motor housing (144) which defines a rest position.
34. 34. Surgical drive system according to sentence 33, characterized in that the control and/or regulation device (12) is designed in the form of a motor control and/or regulation device (12) according to one of sentences 1 to 16.
35. 35. Surgical drive system according to sentence 33 or 34, characterized in that the control and/or regulation device (12) is designed to control and/or regulate the drive unit (14) by means of a method for controlling and/or regulating the drive unit (14 ) after one of sentences 17 to 32.

• 1: eine schematische Übersichtsdarstellung eines chirurgischen Antriebssystems;
• 2: eine schematische Darstellung eines chirurgischen Instruments sowie einer Steuer- und/oder Regelungseinrichtung eines chirurgischen Antriebssystems;
• 3: eine teilweise blockschaltbildartige Darstellung einer Motorsteuerungs- und/oder -regelungseinrichtung zum Ansteuern eines Motors;
• 4: eine schematische Darstellung der Überlagerung von Subphasenwicklungsspannungen zu Wicklungsspannungen bei drei unterschiedlichen Pulsweiten;
• 5: eine Darstellung idealer sinusförmiger Spannungs- beziehungsweise Bestromungskurven der Motorwicklungen;
• 5a: eine vergrößerte Ansicht des Bereichs A in 5;
• 6: eine schematische Darstellung einer Multiphasenübertragungseinrichtung für eine Motorwicklung;
• 7: eine schematische Darstellung einer Bestromung des Elektromotors in einer definierten Ruhestellung oder Parkposition;
• 8: eine vereinfachte, schematische Darstellung der Motorsteuerungs- und/oder -regelungseinrichtung zum Ansteuern des an diese angeschlossenen Elektromotors;
• 9: eine schematische Darstellung des Aufbaus der Motorsteuerungs- und/oder -regelungseinrichtung umfassend eine Motoranhalteeinrichtung; und
• 10: eine schematische ausschnittsweise Schnittansicht einer chirurgischen Antriebseinheit mit Elektromotor mit Rotor und angekoppeltem chirurgischem Werkzeug in der Ruhestellung beziehungsweise Parkposition des Rotors.

The following description of preferred embodiments of the invention is used in connection with the drawing for more detailed explanation. Show it:

• 1 1: a schematic overview representation of a surgical drive system;
• 2 1: a schematic representation of a surgical instrument and a control and/or regulating device of a surgical drive system;
• 3 1: a partially block diagram representation of a motor control and/or regulation device for controlling a motor;
• 4 : a schematic representation of the superimposition of sub-phase winding voltages to winding voltages with three different pulse widths;
• 5 : a representation of ideal sinusoidal voltage or current flow curves of the motor windings;
• 5a : an enlarged view of area A in 5 ;
• 6 : a schematic representation of a multi-phase transmission device for a motor winding;
• 7 : a schematic representation of an energization of the electric motor in a defined rest position or parking position;
• 8th : a simplified, schematic representation of the motor control and/or regulation device for controlling the electric motor connected to it;
• 9 : a schematic representation of the structure of the engine control and/or regulation device comprising an engine stopping device; and
• 10 1: a schematic sectional view of a detail of a surgical drive unit with an electric motor with a rotor and a coupled surgical tool in the rest position or parked position of the rotor.

In 1 is a schematic representation of a surgical drive system provided overall with the reference numeral 10, comprising a control and/or regulating device in the form of a control device 12, five drive units 14a to 14e, two shaver handpieces 16a and 16b, which also form drive units, a pistol handpiece 18, which forms a further drive unit , two connection cables 20 and 22 and a foot control 24.

The control device 12 includes a flat screen 28 arranged in a housing 26 in the form of a touch screen. Three operating elements 30a to 30c and 30d to 30f are arranged on each side of the screen 28 .

Two switches 32a and 32b are arranged below the screen 28 in a line with a connection socket 34 for connecting the foot control 24 via an optional connection cable 25 and with two connection sockets 36a and 36b for connecting the connection cables 20 and 22, with which the drive units are connected to the control unit 12 can be connected. Optionally, a connection 38 for a fluid system for supplying and removing fluids from an operating area can also be provided, for example also for supplying irrigation or suction channels on handpieces or tools (not shown) that can be connected to the drive units 14, the shaver handpieces 16 or the pistol handpiece 18 , with which the drive units form surgical instruments of the drive system 10 together.

The drive units 14a to 14e each include a cable coupling 40a to 40e, which can be connected to a coupling piece 44 of the connecting cable 20 or a coupling piece 46 of the connecting cable 22 as desired. Likewise, the two shaver handpieces 16a and 16b and the pistol handpiece 18 each have a cable coupling 40f, 40g or 40h, which can be connected to one of the two coupling pieces 44 or 46.

At their respective other ends, the drive units 14a to 14e are equipped with handpiece or tool couplings 42a to 42e, to which handpieces (not shown), for example drill handpieces, saw handpieces or the like, can be coupled and driven by the drive units 14a to 14e. Depending on the configuration, the drive units 14a to 14e can also be equipped directly with tools (not shown), such as drills or saw blades, to form surgical instruments.

The drive units are preferably designed without sensors, ie they have no sensors to determine the speed of the drive unit during operation. The drive units of the drive system 10 not only differ, as in 1 shown schematically, externally, but also in terms of their internal structure. This means that the motors installed in the drive units can be of different types and can differ, for example, in their parameters, such as minimum speed, maximum speed, maximum current and maximum torque. In addition, as with the two shaver handpieces 16a and 16b, gears can be integrated, which can optionally also be integrated in handpieces that can be coupled to the drive units 14 and to the pistol handpiece 18 . Depending on the configuration, the handpieces themselves can also be equipped with different instrument tips in the form of surgical tools.

Furthermore, the shaver handpieces 16a and 16b each have a shaver coupling 48a or 48b for connecting a shaver, for example for use in arthroscopy.

The connection cables 20 and 22 are provided with couplings 21 and 23 for connection to the control unit, via which they can be connected to the connection sockets 36a and 36b.

The foot control 24 is connected to the control device 12 via a wireless data transmission device, for example via an infrared or radio transmission system. Optionally, the foot control 24 can also be connected via a coupling piece 50 of the connection cable 25 that can be connected to the connection socket 34 . Two foot-operated switches 54a and 54b are arranged on a housing 52 of the foot control 24, via which in particular counterclockwise or clockwise rotation of the drive units can be regulated.

The pistol handpiece 18 is equipped with two transmitters 56, whereby transmitter 56a can be provided, for example, for activating clockwise rotation of the motor, and transmitter 56b can be provided for activating counterclockwise rotation of the motor.

The connection cables 20 and 22 differ in that, unlike the connection cable 20, an actuating lever 58 is provided on the connection cable 22, with which an operator can activate motor operation of a drive unit 14, a shaver handpiece 16 or the pistol handpiece 18.

In 2 the structure of a surgical instrument 60 is shown schematically. It comprises a drive unit 14, for example a drive unit 14a to 14e, and a tool 64 which can be connected to a coupling 62 on the distal side of the same, for example in the form of a 2 illustrated drill.

A motor 68 is arranged in a housing 66 of the drive unit 14 and has three connection contacts 70a, 70b and 70c, which are each connected to two of the total of three motor windings 72a, 72b and 72c. Terminal 70a is connected to motor windings 72b and 72c, terminal 70b to motor windings 72a and 72b, and terminal 70c to motor windings 72a and 72c.

The connection contacts 70a, 70b and 70c are connected by means of connecting lines 74a, 74b and 74c to a coupling element 76 arranged on the proximal side, specifically to its connecting contacts 78a, 78b and 78c. The coupling element 76 is designed to be connected to the coupling piece 44 of the connection cable 20 in a manner corresponding thereto.

The connection cable 20 itself is a three-wire connection cable with three individual conductors 20a, 20b and 20c. At the in 2 illustrated embodiment, no control or data lines are provided on the connection cable 20 or on the drive unit 40 .

A motor identification device 80 is optionally also integrated into the motor 68, for example from FIG DE 20 2008 006 868 U1 known.

The control unit 12 includes an engine control and/or regulation device 82 arranged in the housing 26, which is referred to below as the control device 82 for the sake of simplicity. It can be used to control the motor 68, which generally includes M motor windings, also referred to as R _{MW_1} , . . . , R _{MW_M} . In the embodiment described below, the number M of motor windings is three and the motor windings are designated 72a, 72b and 72c.

The control device includes a controller 84 which is connected to a digital signal processor 86 . The digital signal processor 86 is in turn coupled to a freely programmable integrated circuit (88) in the form of an FPGA. This serves to control three FET driver circuits 90a, 90b and 90c. The FET driver circuits 90a, 90b and 90c are each connected to a final stage power circuit 92a, 92b and 92c each comprising three identical amplifier circuits 94a, 94b and 94c. A power supply unit 96 is provided for supplying energy to the control device 82 or the drive system 10 and provides the supply voltages correspondingly required for all circuits and elements of the control device 82 .

Each output stage circuit 92a, 92b and 92c is interconnected with an associated multiphase transmission device 98a, 98b and 98c, which is in the form of a multiphase transformer 100a, 100b and 100c, respectively. The multi-phase transformers 100a, 100b and 100c are all constructed identically and are exemplified in connection with 6 explained in more detail below with reference to the multi-phase transformer 100a.

The multi-phase transformer 100a includes three individual transformers 102x, 102y and 102z. These are formed by two coils inductively coupled to one another, namely a primary coil 104x, 104y and 104z and a secondary coil 106x, 106y and 106z. Each primary coil 104x, 104y and 104z includes a primary input 108x, 108y and 108z and a primary output 110x, 110y and 110z. Furthermore, each secondary coil 106x, 106y and 106z includes a secondary input 112x, 112y and 112z and a secondary output 114x, 114y and 114z.

Each of the primary inputs 108x, 108y, 108z is electrically conductively connected to an output of one of the three amplifier circuits 94a. The three secondary inputs 112x, 112y and 112z are electrically connected to each other and to a connection contact 116a of the connection socket 36a, which further comprises two further connection contacts 116b and 116c, which are connected to the multiphase transformers 100b and 100c in an analogous manner. The primary output 110x is electrically conductively connected to the secondary output 114y, the primary output 110y to the secondary output 114z and the primary output 110z to the secondary output 114x. In this way, the individual transformers 102x, 102y and 102z defining the individual phase transmission devices 118x, 118y and 118z are connected in a star configuration, so that the primary coil 104x, 104y, 104z, also referred to as the primary circuit, of each individual phase transmission device 118x, 118y and 118z is connected to the secondary coil 106x, 106y , 106z, also referred to as the secondary circuit, which is connected in series to the respective next single-phase transmission device 118y, 118z and 118x.

The individual transformers 102x, 102y and 102z are connected in such a way that the following applies to their output voltages UxA, UyA and UzA depending on the three input signals U1A, U2A and U3A which are present at the primary inputs 108x, 108y and 108z: $$\text{u}\_\text{A}=1/3\text{u}1\text{A}+1/3\text{u}2\text{A}+1/3\text{u}3\text{A}$$

This superimposition of the input signals U1A, U2A, U3A, U1B, U2B, U3B, U1C, U2C and U3C, i.e. the sub-phase winding voltages, generally represented as U _{MW_1_1} , ..., U _{MW_1_N} , ..., U _{MW_M_1} , ..., U _{MW_M_N} , is an example in 4 shown for three different pulse widths of the input signals. In the 4 The period duration t _x shown is calculated from a clock frequency f _PWM of the PWM method carried out as t _x =1/f _PWM .

A clock generator device of the control device 82, denoted overall by reference numeral 132, is used to specify the PWM clock frequency f _PWM for carrying out the PWM method. The clock generator device includes the controller 84 and the digital signal processor 86. The clock generator device 132 and the signal generation device 120 interact in the control device 82 in such a way that the sub-phase signals, generally referred to as S _{PWM_1_1} , ..., S _{PWM_1_N} ; ...; S _{PWM_M_1} , ..., S _{PWM_M_N} , can be generated with the PWM clock frequency f _PWM . The clock generator 132 preferably generates a PWM clock frequency of 100 kHz.

The digital signal processor 86 forms a signal generating device 120, with which a PWM signal S _{PWM_1} , ..., S _{PWM_M} can be generated for each of the M=3 motor windings R _{MW_1} , ..., R _{MW_M} and with which each of the PWM signals S _{PWM_1} , ..., S _{PWM_M} can be subdivided into N sub-phase signals S _{PWM_1_1} , ..., S _{PWM_1_N} , ..., S _{PWM_M_1} , ..., S _{PWM_M_N} , which in their phase position relative to one another are each rotated by 360°/N , in the embodiment described play with N=3, i.e. by 120°, are offset relative to each other. The signal generating device 120 further includes the circuit 88, which offsets the phase position of the individual sub-phase signals by 120° relative to one another, and the FET driver circuits 90a, 90b and 90c.

The control device 82 also includes a converter device 122, with which the N sub-phase signals assigned to one of the M=3 motor windings 72a, 72b and 72c are converted into N sub-phase winding voltages U _{MW_1_1} , . . . , U _{MW_1_N} ; ...; U _{MW_M_1} , ..., U _{MW_M_N} can be implemented, which are offset in their phase position relative to each other by 360°/N, i.e. by 120° for N=3, with which to generate a current flow I _{MW_1} , ..., I _{MAW_M} through each of the M=3 motor windings R _{MW_1} , ..., R _{MW_M} a winding voltage U _{MW_1} , ..., U _{MW_M} , in 3 represented as U_A, U_B and U_C, can be applied and with which the N subphase winding voltages assigned to one of the M=3 motor windings can be separately superimposed for each of the M motor windings to form the respective winding voltage, which is applied to the respective motor winding to generate the winding current I _{MW_1} , ..., I _{MW_M} , shown in 3 as I_A, I_B and I_C. The converter device 122 comprises the final stage power circuits 92a, 92b and 92c and the multi-phase transmission devices 98a, 98b and 98c. Due to this structure and the interconnection, PWM signals of the same amplitudes or strengths are preferably applied to the three primary inputs 108x, 108y and 108z, but their phase position is offset by 120° in the manner described. These signals are now divided into three and added in multi-phase transformer 100a according to the above formula.

For the calculation of the applied voltages, the following results as an example for the multi-phase transformer 100a: $$\text{u}\_\text{A}=1/3\text{u}1\text{A}+1/3\text{u}2\text{A}+1/3\text{u}3\text{A}$$

$$\text{U}2\text{A}+\text{UyA}-\text{UzA}=\text{U}\_\text{A}$$

$$\text{U}3\text{A}+\text{UzA}-\text{UxA}=\text{U}\_\text{A}$$

The following relationships for the applied voltages result at the individual transformers 102x, 102y and 102z $$\text{u}1\text{A}+\text{UxA}-\text{UyA}=\text{u}\_\text{A}$$

$$\text{u}2\text{A}+\text{UyA}-\text{UzA}=\text{u}\_\text{A}$$

$$\text{u}3\text{A}+\text{UzA}-\text{UxA}=\text{u}\_\text{A}$$

und daraus durch einfache Umformung: $$\text{UyA- UzA= U1A+ U3A- }2\text{U}\_\text{A}$$

UxA is the voltage drop across primary coil 104x and secondary coil 106x, UyA is the voltage drop across primary coil 104y and secondary coil 106y, and UzA is the voltage drop across primary coil 104z and secondary coil 106z. Adding equations (1) and (3) gives $$\text{u}1\text{A}+\text{u}3\text{A}+\text{UzA}-\text{UyA}=2\text{u}\_\text{A}$$

and from this by simple transformation: $$\text{UyA- UzA= U1A+ U3A-}2\text{u}\_\text{A}$$

woraus man erhält: $$\text{U}1\text{A}+\text{U2A}+\text{U3A}=3\text{U}\_\text{A}$$

Inserting this into equation (2) gives: $$\text{U2A}+\text{U1A}+\text{U3A}-2\text{u}\_\text{A= U\_A}$$

from which one obtains: $$\text{u}1\text{A}+\text{U2A}+\text{U3A}=3\text{u}\_\text{A}$$

If U1A = 1 and U2A = U3A = 0, then:

$$\text{UyA- UzA}=1/3$$

$$\text{UzA}-\text{UxA}=1/3.$$

U_A = 1/3. Inserted into equations (1), (2) and (3), this gives: $$2/3+\text{UxA-UyA}=0$$

$$\text{UyA-UzA}=1/3$$

$$\text{UzA}-\text{UxA}=1/3.$$

The voltage relationships of the voltages applied to the individual transformers 102x, 102y and 102z are for three different pulse widths in 4 shown by way of example in the form of the input voltages U1A, U2A and U3A present at the primary inputs, generally the sub-phase winding voltages U _{MW_1_1} , . . . , U _{MW_1_N} ; ...; U _{MW_M_1} , ..., U _{MW_M_N} and the output voltage U_A formed by superimposition.

The voltage jump U_A at the motor winding 72a is only one third of the supply voltage Us, but at three times the frequency f=3*f _PWM . This corresponds to a period T=1/3 t _x , where tx is the period of the PWM signal with the clock frequency f _PWM and is calculated as t _x = 1/f _PWM . For each motor winding 72a, 72b and 72c, also referred to as the motor line, the three multi-phase transmission devices 98a, 98b and 98c are controlled in a corresponding manner.

In order to achieve a sinusoidal curve for the motor voltages U_A, U_B and U_C, as in 5 shown, to generate the pulse width of the corresponding PWM signals is changed accordingly, that is modulated accordingly. By controlling the PWM, for example at 100 kHz, an envelope curve, namely the desired sinusoidal energization curve, is generated for driving the motor 68 . A frequency of 1 kHz of the total sine signal generated by superimposition corresponds to 60,000 revolutions per minute of the motor 68.

The control device 82 thus forms an energization device 124 overall, with which each of the M motor windings can be energized in a sinusoidal or essentially sinusoidal manner, as in FIG 5 shown.

For optimal energization of the motor 68, it is favorable if a rotor position of the rotor relative to the motor windings 72a, 72b and 72c is known. The control device 82 therefore includes a rotor position determination device 126 for determining a rotor position of the electric motor 68 for controlling and/or regulating the M motor windings.

The rotor position determination device 126 includes an energization interruption device 128 which interacts with the energization device 124 . Thus, in order to determine a position of the rotor of electric motor 68, at least one of the M motor windings can be disconnected from an energy supply of control device 82 for a time interval t _interruption . With the rotor position determination device 126, the back EMF, i.e. the voltage induced in the de-energized motor winding, can be measured during the time interval t _interruption , and with a computing unit 130 included in the rotor position determination device 126, an ACTUAL position of the rotor can be determined in a conventional manner from the measured counter EMF are calculated. In particular, the energization of all motor windings can be interrupted simultaneously for the time interval t _interruption by separating the motor 68 from the power supply with the current interruption device 128 . The time interval t _interruption can preferably be specified as constant or as a function of a speed of the motor 68 . The power interruption device 126 is designed in such a way that after the counter-EMF has been measured, all of the motor lines or motor windings 72a, 72b and 72c that are not powered for this purpose are reconnected to the power supply in an electrically conductive manner.

In order to obtain the smallest possible voltage jumps when the current supply to the motor windings is interrupted, the rotor position determination device 126 is designed in such a way that the counter-EMF can only be measured when the respective motor current I_A, I_B or I_C or the motor voltage U_A, U_B or U_C of M motor windings has dropped to zero. In this case, the time interval t _interruption is preferably specified by t _interruption = 2Δt, the measurement of the back EMF at one of the M motor windings being carried out in the time interval t _interruption such that at time t _M the motor voltage present at the motor winding is zero with continuous current flow were.

Switching off the winding voltage on a motor winding is shown in 5A shown in which the voltage drops to zero at time t _M -Δt and is only switched on again at time t _M +Δt. In this way, in the zero crossing of the generated sinusoidal signal, the energization, in particular of the output stage circuits 92a, 92b and 92c, can be interrupted and the measured counter-EMF can be evaluated and further processed for control purposes, in particular via corresponding measuring branches (not shown) of the rotor position determination device 126 connected to the motor windings in cooperation with the controller 84 and the digital signal processor 66.

Control unit 12, i.e. the surgical motor control and/or regulation device, is designed to control and/or regulate drive unit 14 and also includes a motor stopping device 140 for stopping motor 68 down to a speed of zero revolutions per unit of time, for example per minute , in such a way that a rotor 142 of the motor 68 assumes a rotational position relative to a motor housing 144 thereof, which rotational position defines a rest position.

In 10 In a schematic sectional view of motor 68, the rest position or parking position of rotor 142 is symbolized by way of example using two markings 146 and 148, marking 146 being attached to stator 150 of motor 68, marking 148 to rotor 142. Markings 146 and 148 must not necessarily be provided on the engine, they are used in 10 merely to illustrate what is meant by rotational position and rest position within the meaning of this application. Thus, a rotational position can be any orientation of the rotor 142 and thus of the marking 148 in relation to a longitudinal axis 152 of the rotor 142, which at the same time defines an axis of rotation or a drive axis of the motor 68. In principle, any rotary position can also define a rest position. For illustration is in 10 marking 146 is provided to identify a defined rest position of rotor 142 . If the tips of the triangular markings 146 and 148 pointing towards one another are at a minimum distance from one another, the rotor 142 is in the defined rest position. Starting from this rest position, the motor 68 can then start up practically without jerking by applying the appropriate current, as described above, and precisely in the direction of rotation that has been preselected by the user, i.e. either counterclockwise or clockwise rotation of the motor 68.

The controller 12 further includes a direction request memory 154 for storing the last direction request prior to decelerating and stopping the motor 68 to zero RPM speed. A value for counterclockwise rotation or a value for clockwise rotation can therefore be stored in the direction of rotation request memory 154 . The direction of rotation request memory 154 can in particular be directly connected to the controller 84 . Further, the controller 112 may include a home position memory 156 which is also coupled to the controller 84 . Coupled means, in particular, connected in an electrically conductive manner and in this way operatively connected, for example in order to exchange data. In particular, the defined or any desired rest position of the rotor 142 can be stored in the rest position memory 156, for example in the form of an angular value.

The motor stopping device 140 coupled to the controller 84 is designed in such a way that it preferably always keeps the rotor 142 in the same defined rest position.

The controller 12 further includes a mode selector switch 158 which is coupled to the engine stop 140 and allows the engine stop 140 to be selected between two modes of operation. On the one hand, this is a holding mode in which the rotor 142 is actively held in the rest position. This can be done, for example, as in 7 shown schematically below, can be achieved in that two of the motor windings, namely the motor windings 72b and 72c, are switched to circuit ground when the motor 68 is moved into the rest position or into the park position or is held there. The motor winding 72a remains energized and thereby defines a rotational position of the rotor 142 relative to the motor housing 144. For this purpose, the control unit 12 includes a hold-mode energizing device 160, which uses, for example, the components present in the control unit 12 to rotate the motor 68 and its windings 72a, 72b and 72c to be energized in the desired manner. With the holding mode energizing device 160, it is possible to actively hold the rotor 142 in the rest position without rotating it. This is called hold mode.

A hold time specification device 162 for specifying a hold time t _halt during which the motor 68 is continuously energized in order to keep the rotor 142 in the rest position without rotating it is coupled to the hold mode energization device 160 . For example, the hold time specification device 162 can be used to specify a hold time t _hold in a range from 0 minutes to 20 minutes. The hold time t _hold can be set at the factory or specified by a user of the drive system 10 using a corresponding selector switch 164 .

The holding mode energizing device 160 preferably comprises a motor current limiting device 166 for limiting a motor current in order to actively keep the rotor 142 in the rest position without twisting it. For example, the motor current limiting device 166 can be used to limit a motor current to a maximum of 20% of a nominal value of the motor 68 in the holding mode. Preferably, however, the motor current is limited to 15%, more preferably only 10%, of the motor 68 nominal value.

Alternatively, a standby mode of the engine stopping device 140 can also be selected with the mode selector switch 158 . In the stand-by mode, the motor 68 is supplied with current in a defined manner at a rotational speed requirement of 0 revolutions per unit of time after a rest period t _rest for a time t _set to bring the rotor 42 back into the rest position. This can be done within one full revolution of the rotor 142 about the longitudinal axis 152 . However, there can also be a maximum of two or a maximum of three or even more revolutions that the rotor 142 performs in order to return to the position shown in FIG 10 to be brought to rest position shown schematically.

The engine stopping device 140 can in particular be designed as shown schematically in 7 It is shown that the motor winding 72a is repeatedly energized cyclically for a positioning time t _Stell in order to bring the electric motor 68 back into the rest position. Between each adjustment phase, all motor windings 72a, 72b and 72c then remain without current for the idle time t _idle .

Coupled to the engine stopping device 140 is a speed limiter 168 for limiting a maximum speed of the rotor 142 in the standby mode. The maximum speed can be five revolutions per minute, for example. The rotor 142 then rotates very slowly about the longitudinal axis 152, while it is transferred to the rest _{position in the setting time t set} . In this way, personal injury can be avoided.

A standby time t standby of the standby mode can be specified with a standby time specification device 170 of the control unit 112, which is coupled to the engine _stopping device 140. The standby time t _standby can include four positioning cycles, for example, as is shown schematically in 7 is shown. The stand-by time t _stand- by can be set at the factory or via a corresponding one Selector switch 172 can be freely selected by a user of the drive system 10. The standby time t _standby can preferably be specified in a range from 0 minutes to 20 minutes.

A user can use the mode selector switch 158 to manually select the respectively desired operating mode. This means that a user can optionally switch between the standby mode and the hold mode in particular.

The motor stopping device 140 can also include a switching device 174, which is designed to switch at least once after the holding time t _Halt has elapsed from the holding mode to the standby mode. This can happen automatically. This switchover can also take place several times, for example whenever the hold time t _hold has expired. Conversely, the switching device 170 can also be designed for automatic switching at least once after the stand-by time t stand-by _{has elapsed} from the operating mode to the hold mode.

As schematic in 8th shown, to determine the rest position of the rotor 142, a measurement of individual currents and voltages in the motor windings 72a, 72b and 72c is carried out in order to determine, in particular to calculate, that rotational position which the rotor 142 assumes when it is stationary. It can always be the same rotary position, which is then defined as the rest position, or a different one, which is then individually defined as the rest position and stored in the rest position memory 156 .

The motor stopping device 140 can also be used in particular to transfer a tool 176 coupled to the drive unit 14, for example in the form of a shaver 178, into a defined rest position. For example, the shaver 178 has an elongate, tubular shaft 180 in which a force-transmitting member (not shown in detail), which is rotated by the drive unit 14, is mounted in a rotating manner. At a distal end of the shank 180 there is an opening 182 pointing essentially to the side, from which a tool element 184, such as is designed in the form of a blade 186 in a shaver 178, partially protrudes, depending on a rotational position of the force transmission element to cut tissue. With knowledge of a position of the rotor 142 and, if necessary, a gear reduction of a transmission optionally configured between the drive unit 14 and the tool 176, the tool element 184 can thus also be moved into a defined position relative to the opening 182. For example, the engine stopping device 140 can then be used to specify whether the opening 182 is released by the tool 176 or not. In other words, the tool element 184 can either be positioned or parked in a defined manner such that the opening 182 remains free or is closed.

The control unit 12 of the drive system 10 can thus be used to carry out a method for controlling and/or regulating the drive unit 14, in which, when the motor 68 is braked down to a speed of zero revolutions per minute, the electric motor 68 is stopped in such a way that the rotor 142 assumes a rotational position relative to the motor housing 144 or to the stator 150, which defines a rest position.

Claims (22)

Surgical motor control and/or regulation device (12) for controlling and/or regulating a surgical drive unit (14) with a sensorless electric motor (68) which has a motor housing (144), a rotor (142) and at least two motor windings (72a, 72b, 72c), which motor control and/or regulation device (12) is designed to control and/or regulate the drive unit (14) by means of a method for controlling and/or regulating the drive unit (14), characterized by - a motor stopping device (140) to stop the electric motor (68) down to a speed of zero revolutions per unit of time in such a way that the rotor (142) assumes a defined rotational position relative to the motor housing (144), which defines a rest position, and - a standby mode in which the electric motor (68) at a speed requirement of zero revolutions per unit of time after a rest period t _rest , in which the at least two motor windings (72a, 72b, 72c) are not energized, is energized for as long as defined in order to rotate the rotor (142) of the electric motor ( 68) automatically, i.e. without a speed request, after at least one full revolution to return to the rest position. Surgical motor control and/or regulation device according to US Pat claim 1 , characterized by a direction of rotation request memory (154) for storing the last direction of rotation request before braking the electric motor (68) to the speed of zero revolutions per unit time. Surgical motor control and/or regulation device according to one of the preceding claims, characterized in that the motor stopping device (140) is designed in such a way det is that it always stops the rotor (142) in the same rest position. Surgical motor control and/or regulation device according to one of the preceding claims, characterized by a holding mode in which the rotor (142) is actively held in the rest position. Surgical motor control and/or regulation device according to US Pat claim 4 , characterized by a holding mode energizing device (160) for energizing the electric motor (68) in the holding mode in order to actively hold the rotor (142) in the rest position without twisting it. Surgical motor control and/or regulation device according to US Pat claim 4 or 5 , characterized by a holding time setting device (162) for setting a holding time t _stop during which the electric motor (68) is continuously energized in order to keep the rotor (142) in the rest position without twisting it. Surgical motor control and/or regulation device according to any one of Claims 4 until 6 , characterized by a motor current limiting device (166) for limiting a motor current in order to actively keep the rotor (142) in the rest position, without twisting it, to a maximum of 20% of the nominal value of the electric motor (68). Surgical motor control and/or regulation device according to one of the preceding claims, characterized in that it is designed in such a way that in the standby mode the rotor (142) is repeatedly brought back into the rest position. Surgical motor control and/or regulation device according to one of the preceding claims, characterized by a standby time specification device (170) for specifying a standby time t _standby of the standby mode. Surgical motor control and/or regulation device according to US Pat claim 9 , characterized by a switching device (174) for switching at least once after the stand-by time t _stand-by from the stand-by mode to the hold mode. Method for controlling and/or regulating a surgical drive unit (14) with a sensorless electric motor (68) which comprises a motor housing (144), a rotor (142) and at least two motor windings (72a, 72b, 72c), characterized in that when the electric motor (68) is braked down to a speed of zero revolutions per unit of time, the electric motor (68) is stopped in such a way that the rotor (142) assumes a defined rotational position relative to the motor housing (144), which defines a rest position, and that in a stand-by mode of the electric motor (68) when there is a speed requirement of zero revolutions per time unit after a rest period t _rest , in which the at least two motor windings (72a, 72b, 72c) are not energized, the electric motor (68) is energized for a defined period of time to Rotor (142) of the electric motor (68) automatically, namely without speed request, to be converted back into the rest position after at least one full revolution. procedure after claim 11 , characterized in that the last direction of rotation request before braking the electric motor (68) to the speed of zero revolutions per unit time is stored. Procedure according to one of Claims 11 or 12 , characterized in that the rotor (142) in the rest position always occupies the same rotational position relative to the motor housing (144). Procedure according to one of Claims 11 until 13 , characterized in that in a holding mode of the electric motor (68), the rotor (142) is actively held in the rest position. procedure after Claim 14 , characterized in that the electric motor (68) is energized in the holding mode in order to actively hold the rotor (142) in the rest position without twisting it. procedure after Claim 14 or 15 , characterized in that the electric motor (68) is continuously energized during a holding time t _Halt in order to hold the rotor (142) in the rest position without twisting it. Procedure according to one of Claims 14 until 16 , characterized in that a motor current in order to actively keep the rotor (142) in the rest position without twisting it is not more than 20% of the nominal value of the electric motor (68). procedure after Claim 17 , characterized in that in the standby mode the rotor (142) is repeatedly transferred to the rest position. Procedure according to one of claims 17 or 18 , characterized in that the electric motor (68) for a standby time t _standby assumes the standby mode. procedure after claim 19 , characterized in that the electric motor (68) changes from the standby mode to the _hold mode at least once after the standby time t standby has expired. Surgical drive system comprising at least one control and/or regulation device (12) and at least one surgical drive unit (14) that can be connected and controlled thereto and/or at least one surgical instrument (176) comprising a surgical drive unit (14), the at least one drive unit (14) comprises a sensorless electric motor (68) with a rotor (142) and at least two motor windings (72a, 72b, 72c), characterized in that the control and/or regulating device (12) in the form of a motor control and/or - control device (12) according to one of Claims 1 until 10 is trained. Surgical propulsion system Claim 21 , characterized in that the control and / or regulating device (12) is designed to control and / or regulate the drive unit (14) by means of a method for controlling and / or regulating the drive unit (14) according to one of Claims 11 until 20 .

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