Drive and supply unit for implanting dental implants

Abstract

The invention relates to various embodiments of a drive and supply unit (1) for implanting dental implants, which unit can be held with one hand. According to one embodiment, the drive and supply unit (1) comprises an adjustment device (77) for adjusting different transmission ratios such that a handpiece or contra-angle handpiece (7) that can be connected to the drive and supply unit (1) can be operated at different rotational speeds. According to another embodiment, the drive and supply unit (1) comprises three connection devices (6, 8, 9) for connecting a dental handpiece or contra-angle handpiece (7), a battery (10), and a cooling-fluid container (11), wherein the three connection devices (6, 8, 9) are individual, physically separate connection devices. A further embodiment relates to a liquid container (11) which can be connected to the drive and supply unit (1) and comprises a flexible bag (53) in which the liquid (54) is accommodated, a pressurised gas (55) which is provided outside the bag volume (56), and a valve (57) with a valve tube (58).

Description

Preferably, the second or third coupling device arranged offset from and / or outside the sectional plane, in particular the third coupling device for detachably coupling a liquid container or cooling fluid container and / or a liquid container or cooling fluid container connected thereto, is provided between the two coupling devices arranged in the sectional plane. Additionally, or alternatively, the second or third coupling device arranged offset or laterally relative to the sectional plane, in particular the third coupling device for detachably coupling a liquid container or cooling fluid container, is provided between the two coupling devices arranged in the sectional plane with respect to the longitudinal axis. Particularly preferably, the second or third coupling device, in particular the third coupling device, is arranged set back relative to the first coupling device for detachably coupling a dental handpiece or contra-angle handpiece or arranged offset in the direction of the other, preferably the second, coupling device. Among other things, these features form, preferably on an end surface of the outer sleeve, a free space which is bounded on a first side by the protruding, and preferably laterally offset, first coupling device and on a further, second side by the second or third coupling device, in particular the third coupling device. During proper use of the drive and supply unit, a part of the user's hand is accommodated in this free space, preferably the drive and supply unit or the dental implantation device can be supported on a part of the hand received in the free space, for example the back of the hand and / or the wrist, wherein the handling and ergonomics of the drive and supply unit are further improved in an advantageous manner. Preferably, a central plane extends through the drive and supply unit, wherein the first coupling device is arranged on a first side of the central plane and the second and third coupling devices are arranged on another, second side of the central plane. Preferably, the central plane is arranged perpendicular or substantially perpendicular to the sectional plane. Through these features, an unobstructed view of the first coupling device and a handpiece or contra-angle handpiece connected thereto and of the treatment site is advantageously ensured for the user. Preferably, the electric motor and optionally a transmission are arranged adjacent to the first coupling device and / or in alignment with the first coupling device. The transmission is provided in particular for changing the rotational speed and / or the torque of the rotational movement generated by the electric motor. Preferably, the first coupling device and the electric motor and optionally the transmission have a common central axis around and / or along which they are arranged. These features provide structural, for example space-saving, and assembly-related advantages. Preferably, the electric motor is arranged with the first coupling device and optionally the transmission on the first side of the central plane. In particular, the electric motor and optionally the transmission are arranged with respect to the second coupling device and / or a battery connected to the second coupling device and / or the third coupling device and / or a liquid container or cooling fluid container connected to the third coupling device in such a way that the central plane extends between the electric motor on the first side of the central plane and the second coupling device and / or the battery connected to the second coupling device and / or the third coupling device and / or a liquid container or cooling fluid container connected to the third coupling device on the second side of the central plane. The second and third coupling devices are thus in particular located on the second side of the central plane. Through these features, an unobstructed view of the first coupling device and a handpiece or contra-angle handpiece connected thereto and of the treatment site is advantageously ensured for the user. Preferably, the control device for controlling the drive and supply unit comprises a circuit board which is arranged between the electric motor and the second coupling device, in particular a receptacle of the second coupling device, and / or a battery connected to the second coupling device. Preferably, the circuit board has a plurality of sections which are arranged at an angle other than 0° relative to one another, wherein at least one section is arranged between the electric motor and the second coupling device and / or a battery connected to the second coupling device. Particularly preferably, the circuit board or at least one section thereof is arranged parallel to the central plane and / or extends in the central plane. These features result in a space-saving arrangement of the control device, in particular the circuit board, in the outer housing of the drive and supply unit. Preferably, the second coupling device has an opening and a, preferably cylindrical, receptacle into which the battery can be inserted. Preferably, the opening is arranged at the second end or a second end face of the outer housing. Preferably, the opening and / or receptacle is arranged in the sectional plane and / or the sectional plane passes through the opening and / or receptacle. Preferably, the receptacle is dimensioned such that it surrounds at least a part of the battery or the entire battery. Preferably, a closure, for example a lid, is provided at the end of the opening, which closes the opening. Preferably, electrical contacts are provided in the receptacle, in particular opposite the opening, for electrical connection with and / or transmission of electrical energy from the battery to the drive and supply unit, in particular the electric motor. These features advantageously guarantee a reliable and secure energy supply of the drive and supply unit. Preferably, the third coupling device has an opening and a, preferably cylindrical, receptacle into which the liquid container or cooling fluid container can be inserted. The opening may be arranged at the second end or the second end face of the outer housing. Alternatively, the opening of the third coupling device is arranged, as described above for the third coupling device, between the first and second coupling devices and / or laterally offset relative to the longitudinal axis or sectional plane and / or outside the sectional plane. Preferably, the receptacle is dimensioned such that it surrounds at least a part of the liquid container or cooling fluid container or the entire liquid container or cooling fluid container. Preferably, the third coupling device comprises a fluid-transmitting interface for connection to a liquid container or cooling fluid container, via which liquid from the liquid container or cooling fluid from the cooling fluid container can be transferred into the drive and supply unit. Particularly preferably, the fluid-transmitting interface is provided opposite the opening of the third coupling device. These features advantageously guarantee reliable and secure conduction of the liquid or cooling fluid into the drive and supply unit. Particularly preferably, the fluid-transmitting interface comprises at least one liquid or fluid line extending from the third coupling device, in particular from the fluid-transmitting interface, to the first coupling device and via which liquid or cooling fluid can be transferred from the liquid container or cooling fluid container connected to the third coupling device to the handpiece or contra-angle handpiece 12 connected to the first coupling device. The liquid or fluid line preferably extends completely and / or over its entire length within the drive and supply unit and / or the outer housing. These features, in particular the provision of the liquid or fluid line in the outer housing, advantageously facilitate handling of the drive and supply unit and / or the dental implantation device because the user does not have to pay attention to liquid or fluid lines extending outside the drive and supply unit. Preferably, the first coupling device has a coupling pin or a coupling tube onto which the handpiece or contra-angle handpiece can be plugged in to transmit fluid and driving force. Preferably, the coupling pin or coupling tube is arranged at the first end or the first end face of the outer housing. Preferably, the coupling pin or coupling tube is arranged in the sectional plane and / or the sectional plane passes through the coupling pin or coupling tube. Preferably, the coupling pin or coupling tube is configured hollow, such that a shaft of the handpiece or contra-angle handpiece and / or of the electric motor extends into the coupling pin or coupling tube in order to transmit a rotational movement and / or torque generated by the electric motor to the handpiece or contra-angle handpiece and a dental tool connectable thereto. Preferably, a further fluid-transmitting interface for transferring the liquid or cooling fluid from the drive and supply unit to the handpiece or contra-angle handpiece is provided on the coupling pin or coupling tube. In particular, the fluid-transmitting interface is connected to the liquid or fluid line in a fluid-transmitting manner. The fluid-transmitting interface comprises, for example, a bore in the coupling pin or coupling tube. These features advantageously enable a reliable connection of the handpiece or contra-angle handpiece to the drive and supply unit and reliable transmission of the liquid or cooling fluid and the rotational movement and / or torque. The battery may optionally be configured as a non-rechargeable primary battery or, advantageously regarding environmental impact, as a repeatedly rechargeable accumulator. For charging the accumulator, the latter is preferably detachable from the drive and supply unit, in particular the second coupling device, and connectable to a separate charger independent of the drive and supply unit. Alternatively, it is also possible for the drive and supply unit to have charging contacts which can be connected to a charger and / or to an electrical power supply network, such that advantageously the accumulator does not have to be detached from the drive and supply unit for charging. All three coupling devices are preferably configured as detachable coupling devices such that the component assigned to the respective coupling device (handpiece or contra-angle handpiece; battery; liquid container or cooling fluid container) is detachable from the coupling device and / or exchangeable. At least one of the coupling devices is configured, for example, as a plug connection, threaded connection, bayonet connection or similar detachable connection, wherein the user is advantageously enabled to easily and rapidly connect, detach and / or replace the respective component. From the foregoing it can be seen that all three coupling devices are combined in or on the outer housing. The outer housing is preferably configured as a common outer housing for all three coupling devices. In particular, the outer housing connects and / or comprises and / or integrates the three coupling devices such that the drive and supply unit for the implantation of dental implants forms a compact unit which fits well in the hand and is easy to handle. A dental implantation device comprises a handheld drive and supply unit as described above and throughout the document, as well as a handpiece or contra-angle handpiece, a battery and a liquid container or cooling fluid container. Preferably, the handpiece or contra-angle handpiece is detachably 13 couplable to the first coupling device, the battery is detachably couplable to the second coupling device, and the liquid container or cooling fluid container is detachably couplable to the third coupling device. According to an embodiment, a handheld drive and supply unit for implanting dental implants comprises an outer housing, which separates the drive and supply unit from the surroundings, an electric motor arranged in the outer housing for the rotational drive of a dental tool, and a control device arranged in the outer housing for controlling the drive and supply unit. A first coupling device for releasably coupling a dental handpiece or contra-angle handpiece to the drive and supply unit, for mechanically transmitting a rotational drive movement generated by the electric motor to a shaft in the handpiece or contra-angle handpiece, and for conducting a cooling fluid from the drive and supply unit into the handpiece or contra-angle handpiece is furthermore provided on the outer housing. A second coupling device provided on or in the outer housing enables releasable coupling of a battery for supplying the electric motor with electrical energy, and a third coupling device provided on or in the outer housing serves for releasably coupling a cooling fluid container. A transmission or gear unit is furthermore arranged in the outer housing, which is operatively connected to the electric motor in order to receive the rotational drive movement generated by the electric motor and to change the rotational speed and / or the torque of the received rotational drive movement. A shaft arranged in the outer housing or a shaft section of a shaft train is operatively connected to the electric motor in order to transmit the rotational drive movement generated by the electric motor via the first coupling device to the dental handpiece or contra-angle handpiece. Furthermore, an adjusting device for setting different transmission ratios is provided in the outer housing. The adjusting device is configured such that it selectively (i) for setting a (first) transmission ratio couples the shaft to the transmission, such that a rotational drive movement having the rotational speed modified by the transmission is transmittable via the shaft and the first coupling device to the dental handpiece or contra-angle handpiece, or (ii) for setting a further (second, different) transmission ratio decouples the shaft and the transmission, such that the rotational drive movement having the rotational speed generated by the electric motor is transmittable (directly) via the shaft and the first coupling device to the dental handpiece or contra-angle handpiece. Preferably, the different embodiments of handheld drive and supply units described in this document also comprise an adjusting device for setting different transmission ratios and optionally also the transmission or gear unit described below, in particular a planetary transmission. Providing such an adjusting device for setting different transmission ratios considerably facilitates operation of the drive and supply unit or the dental implantation device for users: the implantation of a dental implant comprises several steps, wherein, with respect to the dental implantation device, in particular the handheld drive and supply unit and the handpiece or contra-angle handpiece, essentially two steps having different requirements are to be mentioned, namely firstly drilling into the jawbone in order to create a bore for receiving the implant, and secondly the subsequent insertion or implantation of the implant into this bore. Different rotational speeds and torques are necessary for these two steps, such that a user is forced to use different handpieces or contra-angle handpieces having different transmission ratios. This means that the user has to interrupt the workflow in order to disconnect the contra-angle handpiece required for drilling from the drive motor and to couple the contra-angle handpiece for setting the implant to the drive motor. By arranging the adjusting device in a handheld drive and supply unit, the necessary replacement of the contra-angle handpiece is now advantageously 14 eliminated. Owing to the different transmission ratios that can be realized with the aid of the adjusting device, the user can therefore both produce the bore in the jawbone and set the implant with a single contra-angle handpiece. In contrast to the prior art, the adjusting device and in particular also the transmission is thus advantageously not arranged in the handpiece or contra-angle handpiece. For setting the different transmission ratios, a shaft or a shaft section, which is operatively connected to the electric motor in order to transmit the rotational drive movement generated by the electric motor via the first coupling device to the dental handpiece or contra-angle handpiece, is movable, in particular displaceable or slidable, relative to the transmission or a transmission element. The shaft or the shaft section is particularly preferably axially displaceable relative to the transmission, with respect to a central axis of the transmission or of the coupling pin or of the electric motor. The shaft or the shaft section is preferably (axially) slidable by the adjusting device. The shaft or the shaft section is preferably (axially) slidable within and / or relative to the outer housing. The shaft or the shaft section may be configured as a solid shaft or hollow shaft or may comprise a blind bore. Thus, according to this embodiment it is advantageously not necessary to move the transmission or individual transmission elements axially and / or radially for setting the different transmission ratios. The transmission or individual transmission elements are thus advantageously configured to be immovable for selecting the different transmission ratios. The shaft is preferably part of a shaft train which connects the electric motor to the dental handpiece or contra-angle handpiece via the first coupling device for transmitting the rotational drive movement generated by the electric motor. The movable shaft may thus also be configured as a shaft section of the shaft train, wherein in this document the terms shaft and shaft section are used synonymously. It is essential that the shaft or the shaft section is (axially) displaceable or slidable relative to the transmission in order to be able to set the different transmission ratios. The shaft or the shaft section preferably comprises a first driver element and a second driver element, wherein the shaft and the first and second driver elements are jointly, and in particular simultaneously, movable, or slidable by the adjusting device. The first and second driver elements comprise, for example, a pin, a bolt or a receptacle for a pin or bolt, for example a recess. The pin or bolt preferably passes through the shaft and / or projects beyond the (cylindrical) outer circumference of the shaft or the shaft section. In particular, the first and second driver elements are arranged spaced apart from one another on the shaft. In particular, the first and second driver elements are arranged axially offset on the shaft with respect to a central axis of the transmission or of the coupling pin or of the electric motor. The shaft and the first and second driver elements thus advantageously form a robust and simple assembly that enables reliable setting of the different transmission ratios. Preferably, through the joint movement of the shaft, first driver element and second driver element, either the first driver element couples with a first counter-driver element or the second driver element couples with a second counter-driver element, whereby the different transmission ratios can be set. The first and second counter-driver elements comprise, for example, a pin, a bolt or a receptacle for a pin or bolt, for example a recess. The first and second counter-driver elements are preferably arranged on different components of the drive and supply unit. The first and second counter-driver elements are preferably arranged spaced apart from one another, in particular axially spaced apart with respect to a central axis of the transmission or of the coupling pin or of the electric motor. A counter driver element is preferably provided on a shaft that is connected directly to the electric motor for transmitting the rotational drive movement (i.e., without interposition of the transmission). A counterdriver element is preferably provided on a component of the transmission or on a component connected to the transmission, for example a shaft or a bushing. The pin or bolt preferably passes through the shaft or component and / or projects beyond the (cylindrical) outer circumference of the shaft or component. The first and second counter-driver elements are preferably axially immovable or stationary with respect to a central axis of the transmission or of the coupling pin or of the electric motor. The first and second counter-driver elements are preferably configured to be rotatable about the central axis of the transmission or of the coupling pin or of the electric motor. Particularly preferably, through the joint movement or the joint (axial) displacement of the shaft, first driver element and second driver element, a pin or bolt selectively engages in a receptacle for a pin or bolt, whereby the different transmission ratios can be set. These features advantageously enable a reliable and robust connection of the driver elements and counter-driver elements for setting the different transmission ratios. Preferably, the first driver element and the first counter-driver element connect the shaft or the shaft section directly to the electric motor, without interposition of the transmission, such that the rotational speed and / or the torque of the rotational drive movement generated by the electric motor or of the rotor shaft of the electric motor and the rotational speed and / or the torque of the shaft have the same value. The transmission ratio is thus 1:1. Particularly preferably, the first counter-driver element comprises a pin and the first driver element comprises a receptacle for the pin. Particularly preferably, the first counter-driver element is arranged on the rotor shaft of the electric motor or on a shaft operatively connected to the electric motor or the rotor shaft. In this way, a transmission ratio for drilling the bore in the jawbone for receiving the implant is advantageously provided. Preferably, the second driver element and the second counter-driver element connect the shaft or the shaft section to the transmission, such that the rotational speed and / or the torque of the rotational drive movement generated by the electric motor or of the rotor shaft of the electric motor and the rotational speed of the shaft have different values. The rotational drive movement generated by the electric motor is thus transmitted to the shaft via the rotor shaft of the electric motor and optionally a further shaft connected to the rotor shaft, the transmission, the second driver element and the second counter-driver element. Particularly preferably, the second driver element comprises a pin and the second counter-driver element comprises a receptacle for the pin. Particularly preferably, the second counter-driver element is provided on a bushing that is connected to the transmission, in particular in a rotationally fixed manner. The shaft preferably extends through a bore of the bushing. The transmission is preferably configured as a reduction transmission, for example with a speed increase or reduction ratio of 5:1 or 10:1. The transmission preferably comprises a planetary transmission. In this way, a transmission ratio, in particular a reduction ratio, for inserting the implant into the bore in the jawbone is advantageously provided with a reduced rotational speed value and an increased torque value compared with the rotational speed and torque values generated by the electric motor. Alternatively, the transmission may also be configured as a speed-increasing transmission in which the rotational speed value output by the transmission is increased and the torque value is lower than the rotational speed and torque value generated by the electric motor. Preferably, the pin receptacle of a driver element or of a counter-driver element comprises a recess or a milling, which is provided in an end face of the (cylindrical) shaft or of the (cylindrical) shaft section or of the (cylindrical) bushing connected to the transmission. The end face preferably comprises an apex or apex point which projects beyond the recess, in particular axially with respect to a longitudinal axis of the shaft / bushing or the central axis of the transmission or of the coupling pin or of the electric motor. An inclined plane extends from the apex toward the pin receptacle, in particular the recess, such that the pin slides on the inclined plane into the recess for coupling into the recess if the pin is not immediately received in the pin receptacle when the driver element is connected to the counter-driver element. The inclined plane preferably connects the apex or apex point to the pin receptacle. In this manner, reliable connection or coupling of a driver element or a counter-driver element is advantageously ensured. As already mentioned above, the transmission or gear unit is preferably configured as a planetary transmission. Owing to the movable, displaceable or slidable shaft or the movable, displaceable or slidable shaft section, it is therefore advantageously not necessary, for setting the different transmission ratios, to arrange the planetary transmission or individual components thereof, for example the sun gear, the planet carrier with the planet gears or the ring gear, movably in the outer housing in the axial direction with respect to the central axis of the transmission and / or of the coupling pin and / or of the electric motor. The planetary transmission and / or its components is / are thus, in particular relative to the outer housing, not displaceable, neither axially nor radially. In this manner, switching between the different transmission ratios is advantageously simplified because separation and subsequent re-engagement of components of the planetary transmission, in particular gears, is avoided. The adjusting device for setting the different transmission ratios preferably comprises a cam device, which comprises a cam groove, a cam follower, in particular in the form of a body of revolution, for example a ball, and a control disc having a control track provided on the circumference of the control disc. Providing such a cam device enables smooth and reliable setting of the different transmission ratios. The cam groove is preferably provided in a rotationally fixed inner sleeve. The rotationally fixed inner sleeve preferably comprises the coupling pin or coupling tube. The cam groove is preferably arranged spaced apart from the coupling pin. The cam groove is preferably covered by the outer housing. The cam groove preferably extends radially around the central axis of the transmission and / or of the coupling pin and / or of the electric motor and in particular obliquely offset along the central axis. The cam groove preferably surrounds the central axis in such an offset manner that one end of the cam groove is closer to the transmission, and another end is closer to the coupling pin. The cam groove preferably surrounds the central axis in such an offset manner that one end of the cam groove is further away from the transmission, and another end is further away from the coupling pin. These features bring about reliable setting of the different transmission ratios. The control disc is preferably operatively connected to the shaft or the shaft section. The control disc is preferably arranged within the rotationally fixed inner sleeve, in particular fixed against rotation with respect to the outer housing. The control disc is preferably connected to the shaft such that the control disc, the shaft and the first and second driver elements are jointly movable, in particular axially displaceable, or slidable, and especially simultaneously. The control disc preferably extends in a plane that is arranged orthogonally to the central axis, wherein this plane in particular intersects the cam groove and / or the cam groove is likewise arranged in this plane. These features enable reliable setting of the different transmission ratios. The control track preferably extends only over a portion of the circumference or peripheral surface of the control disc, in particular the ends of the control track enclose an angle between approximately 45° and 90°. The control track is preferably recessed into the outer circumference or peripheral surface of the control disc, for example milled therein. The cam follower preferably extends from an actuating element of the adjusting device, in particular provided on the outer housing, through the cam groove into the control track. By operation of the actuating element, the cam follower can be guided in the cam groove along the central axis of the transmission and / or of the coupling pin and / or of the electric motor owing to the oblique arrangement of the cam groove, whereby the control disc and the shaft connected thereto with the driver element and the counter-driver element are axially displaceable or slidable along the central axis for setting the different transmission ratios. This construction and the described mode of operation of the adjusting device and / or cam device advantageously provide an axially space-saving possibility, with respect to the central axis, for setting the different transmission ratios. The control disc preferably comprises a bore, in particular a central bore, in which the shaft or the shaft section and a rolling bearing, in particular a ball bearing, are received. The rolling bearing in particular rotatably supports the shaft in the control disc. Provision of the rolling bearing thus advantageously results in decoupling between the shaft and the control disc with respect to rotational movement of the shaft while coupling is simultaneously maintained with respect to axial displaceability of the control disc with the shaft. The adjusting device is preferably adjustable via an actuating element that can be actuated by a user. The actuating element is preferably operatively connected to the adjusting device and / or configured as part of the adjusting device. The actuating element that can be actuated by the user is preferably configured to be movable on and / or relative to the outer housing. The actuating element is in particular configured as part of the drive and supply unit. The actuating element preferably comprises a rotary ring, a rotary sleeve or a slider which is rotatable about the central axis of the transmission and / or of the coupling pin and / or of the electric motor. A recess or a milling is preferably provided on the inside of the actuating element, in which the cam follower is received and / or guided, such that upon movement or rotation of the actuating element, the cam follower is entrained and guided in the cam groove, whereby the adjusting device is activated as described above. These features enable the user to conveniently set and select the different transmission ratios. Preferably, a detent device is provided between the actuating element that can be actuated by the user and the rotationally fixed inner sleeve, which detent device is configured to fix the actuating element in a position in which one of the different transmission ratios has been set, in particular to fix it relative to the inner sleeve and / or the outer housing. The detent device preferably comprises a detent body biased by a spring element and a detent recess into which the detent body engages. For example, the spring element and the detent body are provided in the movable actuating element and the detent recess is provided in the rotationally fixed inner sleeve. For example, the spring element and the detent body are provided in the rotationally fixed inner sleeve and the detent recess is provided in the movable 18 actuating element. Such a detent device advantageously fixes the position of the movable actuating element and thus the set transmission ratio and provides the user with haptic feedback that a transmission ratio has been set. The invention is explained below on the basis of preferred embodiments and with reference to the accompanying drawings. Figure 1 shows an embodiment of a handheld drive and supply unit for the implantation of dental implants with a view of a front side or first end face of the drive and supply unit, on which the first coupling device for detachably coupling a dental handpiece or contra-angle handpiece is provided; Figure 2 shows the rear side or second end face of the drive and supply unit of Figure 1, the second coupling device for detachably coupling a battery and the third coupling device for detachably coupling a liquid container or cooling fluid container; Figure 3 shows the drive and supply unit of Figure 1 with coupled handpiece or contra-angle handpiece and liquid container or cooling fluid container; Figure 4 shows the drive and supply unit of Figure 1 with coupled battery and coupled liquid container or cooling fluid container; Figure 5 shows a sectional view of the drive and supply unit of Figure 1; Figure 6 shows the drive and supply unit of Figure 1 in a partially transparent representation; Figure 7 shows an embodiment of a handheld drive and supply unit for the implantation of dental implants having a second coupling device for detachably coupling a battery and a third coupling device for detachably coupling a liquid container or cooling fluid container, each closable by a closure. Figure 8 shows a sectional view of an embodiment of a liquid container that can be coupled to a medical, in particular dental, treatment device, with an unfilled flexible bag; Figure 9 shows a sectional view of the liquid container of Figure 8 with a filled flexible bag; Figure 10 shows a sectional view of one embodiment of a valve of a liquid container that can be coupled to a medical, in particular dental, treatment device; Figure 11 shows a first embodiment of a liquid container with a connector that connects the liquid container to a medical, in particular dental, treatment device in such a manner that liquid can be conveyed from the flexible bag; Figure 12 shows a second embodiment of a liquid container with a connector that connects the liquid container to a medical, in particular dental, treatment device in such a manner that liquid can be conveyed from the flexible bag; Figure 13 shows a sectional view of a third embodiment of a liquid container with a connector that connects the liquid container to a medical, in particular dental, treatment device in such a manner that liquid can be conveyed from the flexible bag; Figure 14 shows a sectional view of a liquid container with a connector that is received in a (third) coupling device of a medical, in particular dental, treatment device and connected to a valve and a liquid line of the medical, in particular dental, treatment device; Figure 15 shows a top view of the liquid container, the connector, the valve, and the liquid line of Figure 14; Figure 16 shows an embodiment of a medical, in particular dental, treatment device in which the liquid is conveyed from the liquid container to the liquid dispensing device via a liquid line that is arranged at least partially outside the outer housing; Figure 17 shows an embodiment of a medical, in particular dental, treatment device in which the liquid is conveyed from the liquid container to the liquid dispensing device via a liquid line that is arranged within the outer housing; Figure 18 shows an embodiment of a medical, endodontic treatment device that can be supplied with liquid from a liquid container having a flexible bag; Figure 19 shows an embodiment of a handheld drive and supply unit for implanting dental implants having an actuating element with which a user can select different transmission ratios; Figure shows 20 a sectional view through the first coupling device provided on the outer housing, the actuating element for setting the adjusting device, the adjusting device for setting different transmission ratios and the transmission or gear unit comprising a planetary transmission, wherein the drive train, which transmits the rotational drive movement generated by the electric motor to a handpiece or contra-angle handpiece, is connected directly (i.e. not via the transmission) to the electric motor (transmission ratio 1:1); Figure 21 shows a sectional view through the first coupling device provided on the outer housing, the actuating element for setting the adjusting device, the adjusting device for setting different transmission ratios and the transmission comprising a planetary transmission, wherein the drive train, which transmits the rotational drive movement generated by the electric motor to a handpiece or contraangle handpiece, is connected to the electric motor via the transmission (transmission ratio not equal to 1:1); Figure 22 shows a further sectional illustration of the actuating element for setting the adjusting device, the adjusting device for setting different transmission ratios and the planetary transmission; Figure 23 shows a perspective illustration of the adjusting device for setting different transmission ratios and of the planetary transmission; Figure 24 shows the slidable shaft of the adjusting device; Figure 25 shows the bushing which is connected rotationally fixed to the transmission in order to selectively connect the transmission to the drive train, which transmits the rotational drive movement generated by the electric motor to a handpiece or contra-angle handpiece. The medical, in particular dental treatment device 100, 25 which comprises for example a handheld drive and supply unit 1 for the implantation of dental implants shown in Figures 1 to 7 comprises an outer housing 2 which separates the drive and supply unit 1 from the surroundings. The outer housing 2 has a plurality of sides or surfaces: an upper side 2A, which, when the drive and supply unit 1 is held correctly, for example during placement of an implant, forms the upper end of the drive and supply unit 1. A human-machine interface 26 may preferably be provided on the upper side 2A, for example an operating element, an adjusting element, or a display. A lower side 2B is arranged opposite the upper side 2A. When the drive and supply unit 1 is held correctly, for example during implantation, the lower side 2B forms the lower end of the drive and supply unit 1. A first end face or first end 2C forms a side wall of the outer housing 2 and thus connects the upper side 2A to the lower side 2B. In particular, a first coupling device 6 is provided at the first end 2C. A second end face or second end 2D forms a further side wall of the outer housing 2 and thus likewise connects the upper side 2A to the lower side 2B. At least one further coupling device, for example a second coupling device 8 or a third coupling device 9, is preferably provided at the second end face 2D. Preferably, the first end face 2C and the second end face 2D are opposite one another. Further side surfaces 2E are provided on the further sides of the drive and supply unit 1, in particular of the outer sleeve 2, which connect both the upper side 2A to the lower side 2B and the first end face 2C to the second end face 2D. The first coupling device 6 arranged on the outer housing 2, in particular on the first end face 2C, is provided for detachably coupling a dental handpiece or contra-angle handpiece 7 (see Figure 3) to the drive and supply unit 1, for mechanically transmitting a rotational drive movement generated by an electric motor 3 (see Figures 5 and 6) to a shaft in the handpiece or contra-angle handpiece 7, and for conducting a liquid or cooling fluid from the drive and supply unit 1 into the handpiece or contra-angle handpiece 7. The first coupling device 6 has a coupling pin 24 onto which the handpiece or contra-angle handpiece 7 can be plugged such that fluid and driving force are transmitted. The coupling pin 24 is rotationally symmetrical and / or cylindrical in shape. Preferably, the handpiece or contra-angle handpiece 7 is rotatably fastened to the coupling pin 24, so that the handpiece or contra-angle handpiece 7 can be rotated relative to the drive and supply unit 1 during dental treatment for improved handling. The coupling pin 24 is configured hollow for receiving a shaft which connects the electric motor to a shaft in the handpiece or contra-angle handpiece 7 and to a dental tool 4. The coupling pin 24 comprises at least one bore through which a liquid or cooling fluid can be transferred from the drive and supply unit 1 into the handpiece or contra-angle handpiece 7. The coupling pin 24 extends, in particular linearly, from the first end face 2C, preferably from a coupling surface 27, along a coupling-pin central axis 28. The coupling surface 27 is preferably configured circular. The coupling pin 24 and in particular the coupling surface 27 are arranged close to one of the side surfaces 2E. The coupling pin 24 and the coupling surface 27 are thus not arranged centrally but offset relative to the center of the end face 2C. The coupling surface 27, in particular its peripheral edge, preferably directly adjoins a side surface 2E, see Figures 2 and 4. Among other things, this lateral arrangement of the coupling pin 24 and / or of the coupling surface 27 forms a free space 29. During intended use and / or correct holding of the drive and supply unit 1 during an implantation treatment, a part of the user's hand is accommodated in this free space 29. A battery 10, in particular a repeatedly rechargeable accumulator, for supplying the electric motor 3 with electrical energy can be detachably connected to the second coupling device 8 provided on or in the outer housing 2, in particular on the second end face 2D. The second coupling device 8 comprises an opening 19 and a cylindrical receptacle 20 into which the battery 10 can be inserted and stored. The cylindrical receptacle 20 may be dimensioned such that it receives only a part of the battery 10, so that a section of the battery 10 projects out of the receptacle 20 and / or the outer housing 2, so that the battery 10 can easily be removed from the receptacle 20 or inserted into the receptacle 20, see Figures 3 and 4. Alternatively, see Figure 7, the receptacle 20 is dimensioned such that it receives and / or encloses the entire battery 10, and is preferably closable by a closure 34, for example a lid, so that the ingress of contaminants into the receptacle 20 is reduced. The closure 34 is movable relative to the opening 19, for example rotatable, screwable, removable or hinged, so that battery 10 can be inserted into and removed from the receptacle 20 without obstruction. The third coupling device 9 provided on or in the outer housing 2 is configured for detachably coupling a liquid container or cooling fluid container 11. The third coupling device 9 has an opening 21 and a, preferably cylindrical, receptacle 22 into which the liquid container or cooling fluid container 11 can be inserted. A fluid-transmitting interface 23 for connection to the liquid container or cooling fluid container 11 is provided on a wall of the third coupling device 9 opposite the opening 21, via which liquid from the liquid container or cooling fluid from the cooling fluid container 11 can be transferred into the drive and supply unit 1. The cylindrical receptacle 22 may be dimensioned such that it receives only a part of the liquid container or cooling fluid container 11, so that a section of the liquid container or cooling fluid container 11 projects out of the receptacle 22 and / or the outer housing 2, so that the liquid container or cooling fluid container 11 can easily be removed from the receptacle 22 or inserted into the receptacle 22, see Figures 3 and 4. Alternatively, see Figure 7, the receptacle 22 is dimensioned such that it receives and / or encloses the entire liquid container or cooling fluid container 11, and is preferably closable by a closure 35, for example a lid, so that the ingress of contaminants into the receptacle 22 is reduced. Closure 35 is movable relative to the opening 21, for example rotatable, screwable, removable or hinged, so that the liquid container or cooling fluid container 11 can be inserted into and removed from the receptacle 22 without obstruction. The first, second and third coupling devices 6, 8, 9 are independent coupling devices separate from one another, which are arranged at different positions of the handheld drive and supply unit 1 and / or of the outer housing 2. The first coupling device 6 for detachably coupling a dental handpiece or contra-angle handpiece 7 and the second coupling device 8 for detachably coupling a battery 10 are arranged at the opposite ends or end faces 2C, 2D. The ends 2C, 2D and / or the first and second coupling devices 6, 8 are arranged along a longitudinal axis 30 extending through the drive and supply unit 1. The first and the second coupling devices 6, 8, preferably also the handpiece or contra-angle handpiece 7 and the battery 10, are arranged around the longitudinal axis 30 such that the longitudinal axis 30 extends between these components 6, 8, 7, 10. As can be seen from Figures 5 and 6, further components of the drive and supply unit 1 are arranged along or around the longitudinal axis 30, for example the electric motor 3 and / or a transmission 31. The electric motor 3, the transmission 31 and the first coupling device 6 are arranged along a coupling-pin / electric-motor central axis 28, which in particular also forms the axis of rotation of the electric motor 3, wherein a compact drive unit is formed. The battery 10 is arranged below the electric motor 3 and / or the transmission 31 and / or the first coupling device 6, see Figure 5. The electric motor 3 and / or the transmission 31 and / or the first coupling device 6 are arranged above the battery 10. The electric motor 3 and / or the transmission 31 and / or the first coupling device 6 on the one hand and the battery 10 on the other hand are arranged in different planes within the outer housing 2. The receptacle 20 and / or the battery 10 have a battery-receptacle central axis 32 which is arranged parallel or substantially parallel to the coupling-pin / electric-motor central axis 28. Through this arrangement of the electric motor 3, the transmission 31 and the first and second coupling devices 6, 8, optionally with the battery 10 and the handpiece or contra-angle handpiece 7, the entire drive train is arranged compactly and linearly in a partial volume of the drive and supply unit 1 or of the outer housing 2. The first coupling device 6 for detachably coupling a dental handpiece or contra-angle handpiece 7 and the second coupling device 8 for detachably coupling a battery 10 are furthermore arranged in a sectional plane 14 through the drive and supply unit 1. The sectional plane 14 extends through the opposite ends 2C, 2D of the drive and supply unit 1 and through the upper side 2A and lower side 2B of the outer housing 2, see Figure 5. The respective axes 28, 30, 32 are arranged in the sectional plane 14 or extend therein. The electric motor 3 and / or the transmission 31 are also arranged in the sectional plane 14 and / or intersected by the latter. The third coupling device 9 for detachably coupling a liquid container or cooling fluid container 11 and / or the liquid container or cooling fluid container 11 accommodated therein is / are arranged offset from and / or outside the sectional plane 14. The third coupling device 9 is arranged offset relative to the first and second coupling devices 6, 8. A fluid central axis 33 of the third coupling device 9 and / or of the liquid container or cooling fluid container 11 is arranged parallel or substantially parallel to the axes 28, 30, 32. The third coupling device 9 is provided (with respect to the longitudinal axis 30) between the two coupling devices 6, 8 arranged in the sectional plane 14. The third coupling device 9 is arranged set back relative to the first coupling device 6 for detachably coupling a dental handpiece or contra-angle handpiece 7 and / or arranged offset in the direction of the second coupling device 8. This set-back arrangement of the third coupling device 9 also forms the free space 29 described above. It can be seen in Figure 6 that a central plane 15 extends through the drive and supply unit 1, wherein the first coupling device 6 for coupling the handpiece or contra-angle handpiece 7 is arranged on a first side 16 of the central plane 15 and the second and third coupling devices 8, 9 are arranged on another, second side 17 of the central plane 15. The central plane 15 is arranged perpendicular or substantially perpendicular to the sectional plane 14. The two receptacles 20, 22 are thus arranged below the central plane 15 and / or substantially adjacent to one another and / or at the end 2D of the drive and supply unit 1. The common provision of the receptacles 20, 22 at the rear end 2D enables unobstructed access to the receptacles 20, 22 and thus uncomplicated replacement of the battery 10 and the liquid container or cooling fluid container 11. The electric motor 3 and the transmission 31 are arranged on the first side 16 of the central plane 15. The electric motor 3 and the transmission 31 are furthermore arranged with respect to the second coupling device 8 and / or a battery 10 connected to the second coupling device 8 and the third coupling device 9 and / or a liquid container or cooling fluid container 11 connected to the third coupling device 9 such that the central plane 15 extends between the electric motor 3 and the transmission 31 on the first side 16 of the central plane 15 and the second coupling device 8 and the third coupling device 9 on the second side 17 of the central plane 15. The second and third coupling devices 8, 9 and / or the respective receptacles 20, 22 are therefore located on the second side 17 of the central plane 15. A control device 5 is furthermore arranged in the outer housing 2 and is provided for controlling the drive and supply unit 1 and / or the handpiece or contra-angle handpiece 7 connected thereto, see Figures 5 and 6. The control device 5 has a circuit board 18 which is arranged between the electric motor 3 and the second coupling device 8, in particular the receptacle 20. The circuit board 18 has a 23 plurality of sections which are arranged at an angle other than 0° relative to one another, wherein at least one section is arranged between the electric motor 3 and the second coupling device 8. At least a section of the circuit board 18 is arranged parallel to the central plane 15 and / or extends in the central plane 15. Figure 3 shows a dental implantation device 25 comprising a handheld drive and supply unit 1 and coupled thereto a handpiece or contra-angle handpiece 7, a battery 10 and a liquid container or cooling fluid container 11. It can be seen that the dental implantation device 25 forms a compact, stable unit which is defined or delimited by the outer housing 2 and on which the three coupling devices 6, 8, 9 are jointly arranged at ergonomically optimized positions. In the following, the structure of the liquid containers or cooling fluid containers 11 shown in Figures 7 to 15 is described, which can be coupled to a medical, in particular dental, treatment device 100, preferably to a cordless treatment device 100, 25, 1 without a line connection to an energy and fluid source arranged outside the outer housing 2, in order to dispense a liquid 54 contained in the liquid or cooling fluid container 11 to the medical, in particular dental, treatment device 100, 25, 1. For the sake of simplicity, the liquid or cooling fluid container 11 is referred to below as the liquid container 11. The liquid container 11 is provided to contain a liquid 54 that can be dispensed by the liquid dispensing device 36, 37 (see Figures 16, 17) of the treatment device 100. The liquid container 11 can be detachably coupled to a coupling device 9 provided on or in the outer housing 2 of the treatment device 100. The liquid container 11 comprises an outer wall 51, preferably cylindrical, which separates an interior container space 52 of the liquid container 11 from the surroundings. Arranged in the interior container space 52 is a flexible bag 53 having a bag volume 56 in which the liquid 54 is received, see in particular Figure 13. Due to its flexible and / or elastic outer shell, the bag volume 56 of the flexible bag 53 is variable; in particular, the flexible outer shell and / or the bag volume 56 substantially adapts to the quantity of liquid received in the flexible bag 53 and / or the bag volume 56 changes in accordance with a change in the quantity of liquid contained in the flexible bag 53. For example, the bag volume 56 decreases when liquid 54 is conveyed from the flexible bag 53, and the bag volume 56 increases when liquid 54 is received in the flexible bag 53. Furthermore, a pressurized gas 55 (see Figure 13) is received in the liquid container 11, said gas being located in the interior container space 52 but outside the bag volume 56. The pressurized gas 55 thus surrounds the flexible bag 53 and any liquid 54 provided therein. In particular, the pressurized gas 55 is provided between the flexible bag 53 and the inner side of the outer wall 51. Depending on the quantity of liquid 54 present in the flexible bag 53 or the liquid container 11, the pressurized gas 55 occupies different volumes within the liquid container 11. For example, the pressurized gas 55 occupies a larger volume in the liquid container 11 when a smaller quantity of liquid 54 is received in the flexible bag 53. For example, the pressurized gas 55 occupies a smaller volume in the liquid container 11 when a larger quantity of liquid 54 is received in the flexible bag 53. Accordingly, the pressure of the pressurized gas 55 decreases when the gas 55 occupies a larger volume in the liquid container 11 and / or a smaller quantity of liquid 54 is received in the flexible bag 53. The pressure of the pressurized gas 55 increases when the gas 55 occupies a smaller volume in the liquid container 11 and / or a larger quantity of liquid 54 is received in the flexible bag 53. The liquid container 11 further comprises a valve 57 with a valve tube 58, which is in fluid communication with the flexible bag 53, in particular the bag volume 56. The valve 57 is switchable between a closed position (see Figure 10), in which the liquid 54 received in the bag volume 56 cannot escape from the flexible bag 53, and an open position (see Figures 13, 14), in which the liquid 54 received in the bag volume 56 can escape from the flexible bag 53 through the valve tube 58. In the open position, the pressure exerted by the pressurized gas 55 on the flexible bag 53, in particular on the liquid 54 received therein, drives the liquid 54 from the flexible bag 53 into the valve tube 58, and in particular further into the medical, in particular dental, treatment device 100, preferably as far as the liquid dispensing device 36, 37 and beyond into the surroundings. The valve shown in Figures 10, 13 and 14 and described below shows one possible embodiment of a valve of the liquid container 11. Of course, there are various other valves or actuating elements that are likewise suitable for permitting reliable, directed conveyance of the liquid 54 from the liquid container 11 only when the liquid container 11 is coupled to the treatment device 100, 25, 1. The valve 57 comprises a movable valve body 59, which is biased by a spring element 69 and / or upon which the pressure of the pressurized gas 55 received in the interior container space 52 acts. In the closed position (see Figure 10), the valve body 59 is pressed by the spring element 69 and / or the gas pressure into a valve seat of the valve 57 and / or in the direction of a sealing element 68 of the liquid container 11. The valve body 59 is connected to the valve tube 58, so that movement of the valve body 59 also moves the valve tube 58 and at least one valve opening 67 arranged in the valve tube 58, through which the liquid 54 can flow from the valve 57 and / or the flexible bag 53 into the medical, in particular dental, treatment device 100, 25, 1. The sealing element 68 is arranged immovably relative to the valve 57, the valve tube 58 and / or the valve opening 67. The sealing element 68 surrounds the valve tube 58 and / or the at least one valve opening 67. The sealing element 68 is configured, for example, as a sealing ring or annular sealing element, wherein the valve tube 58 extends through a central opening of the annular sealing element 68. In the closed position of the valve 57, the valve tube 58, in particular the at least one valve opening 67, is arranged such that the sealing element 68 closes the conveying path of the liquid 54 from the valve 57 and / or through the valve 57 and / or the valve opening 67, such that the liquid 54 cannot be conveyed from or escape from the liquid container 11 (see Figure 10). In the open position, the valve body 59 is moved away from the valve seat of the valve 57 against the force of the spring element 69 and / or the gas pressure of the gas 55 and / or the valve opening 67 is moved into a position in which the sealing element 68 does not close or seal the conveying path of the liquid 54 through the valve 57 and / or the valve opening 67, so that the liquid 54 can flow out of the flexible bag 53 (see Figures 13, 14). The movement of the valve body 59 and the valve tube 58 from the closed position into the open position against the force of the spring element 69 and / or the pressure force of the pressurized gas 55 acting on the valve body 59 is preferably achieved during and / or by the coupling of the liquid container 11 to the coupling device 9. A connector 60 is provided on the liquid container 11 which detachably connects the liquid container 11 to the medical, in particular dental, treatment device 100, 25, 1 in such a manner that the liquid 54 can be conveyed from the flexible bag 53 and through the valve tube 58 into a liquid line 70 of the medical, in particular dental, treatment device 100, 25, 1. The connector 60 comprises a connector 25 body 61 on which a first connection element 62 for connecting the connector 60 to the outer wall 51 of the liquid container 11 (see Figures 13, 14) and a second connection element 63 for connecting to the medical, in particular dental, treatment device 100, 25, 1 are provided (see Figures 11, 12, 13). The first connection element 62 is arranged on an inner side of the connector 60 so that it extends in the direction of the outer wall 51 of the liquid container 11. The connector 60 comprises a circular skirt or a circular skirt-like extension 66 on which, in particular on the inner side thereof, the first connection element 62 is provided or configured as part thereof. The first connection element 62 is in particular configured as a mechanical connection element: it comprises at least one locking lug 65 which engages in a first mating connection element 65A on the outer wall 51, in particular a recess or groove, of the liquid container 11. The first connection element 62 and mating connection element 65A thus form a positive-locking connection 65, 65A between the connector 60 and the liquid container 11; however, other types of connection are of course also possible, in particular a frictionally locking connection. The second connection element 63 for connecting the connector 60 to the medical, in particular dental, treatment device 100, 25, 1 is arranged on an outer side of the connector 60 and / or positioned such that it extends away from the connector body 61 and / or in the direction of the treatment device 100, 25, 1. The second connection element 63 comprises a mechanical, in particular positively locking and / or frictionally locking connection element, for example a bayonet connection with projections 73 on the connector 60 for engagement in a groove on the treatment device 100, 25, 1 (see Figure 11), a thread (see Figure 12) and / or a latching device (see Figure 13), in which a movable latching element 75 of the treatment device 100, 25, 1 engages in a receptacle 74 on the connector 60. A corresponding (second) mating connection element 63A (see Figures 13, 14), for example the above-mentioned groove of the bayonet connection, a thread or the mentioned movable latching element 75, is provided on the medical, in particular dental, treatment device 100, 25, 1, in particular on the (third) coupling device 9 for detachably coupling the liquid container 11, which enters into a connection with the second connection element 63, so that the liquid container 11 is reliably coupled with and by the connector 60, and in particular fluid-tightly coupled to the medical, in particular dental, treatment device 100, 25, 1. The connector 60 is arranged at that end of the liquid container 11 at which the valve 57 is provided, wherein the connector body 61 comprises a passage 64 into which the valve tube 58 and / or a liquid line 70 of the medical, in particular dental, treatment device 100, 25, 1 extends when the liquid container 11 is coupled to the treatment device 100, 25, 1, in particular to the (third) coupling device 9. Passage 64 is bounded by a, preferably cylindrical, wall 64A. The wall 64A surrounds the valve tube 58 and / or the liquid line 70. Preferably, the free end of wall 64A remote from the valve 57 projects beyond the free end of the valve tube 58 remote from the valve 57 and / or the free end of the valve tube 58 remote from the valve 57 extends into passage 64 but not beyond its free end (see Figures 13, 14). Thus, displacement of the valve tube 58 against the spring force of the spring element 69 and / or the gas pressure of the gas 55, and thus the (unintended) dispensing of the liquid 54 from the liquid container 11 when it is not coupled to the treatment device 100, 25, 1, is advantageously at least made more difficult or prevented. Figure 14 schematically shows, in a sectional view, the liquid container 11 with the connector 60, which is received in the (third) coupling device 9 of the medical, in particular dental, treatment device 100, 25, 1 and connected to an actuating element 71, in particular a valve, and a liquid line 70 of the 26 treatment device 100, 25, 1. The liquid container 11 is connected at the fluid-transferring interface 23 via the connector 60, in particular the second connection element 63, to the treatment device 100, 25, 1, in particular the second mating connection element 63A, in such a manner that the liquid 54 can be conveyed from the flexible bag 53 through the valve 57, the valve tube 58 to the valve 71 and, if the valve 71 is open, through the liquid line 70 as far as the liquid dispensing device 36, 37 and into the surroundings, see also Figures 15 and 17. As can be seen from Figure 14, by coupling the liquid container 11 to the treatment device 100, 25, 1, the valve 57 of the liquid container 11 is moved into the open position. This movement is effected by contact of the actuating element or valve 71 and / or the liquid line 70 of the treatment device 100, 25, 1 with the valve tube 58, whereby the valve tube 58 and the valve body 59 of the liquid container 11 are moved in the direction of the flexible bag 53 against the spring force of the spring element 69 and / or the gas pressure of the gas 55. Due to the pressure exerted by the pressurized gas 55 on the flexible bag 53 and the liquid 54 contained therein, liquid now flows, with the valve 57 open, into the valve 57, through the valve tube 58 and at least as far as the valve 71. As long as the liquid container 11 is coupled to the treatment device 100, 25, 1, the valve 57 remains in the open position. If the liquid container 11 is separated from the treatment device 100, 25, 1, the valve tube 58 and the valve body 59 move in the direction of the connector 60 due to the spring force of the spring element 69 and / or the gas pressure of the gas 55, whereby, as described above, the sealing element 68 closes the conveying path of the liquid 54 from or through the valve 57 and / or the valve opening 67, so that the valve 57 assumes the closed position and no liquid 54 can escape from the liquid container. The actuating element 71 provided in the outer housing 2 of the medical, in particular dental, treatment device 100, 25, 1, which in particular comprises a valve, controls conveyance of the liquid 54 from the liquid container 11 and / or dispensing of the liquid 54 via the liquid dispensing device 36, 37. As described above, when the liquid container 11 is coupled to the treatment device 100, 25, 1 and thus the valve 57 of the liquid container 11 is open, the liquid 54 flows at least as far as the valve 71. If the valve 71 assumes an open position, conveyance of the liquid 54 through the liquid line 70 and the liquid dispensing device 36, 37 and dispensing into the surroundings is possible. If the valve 71 assumes a closed position, conveyance and dispensing of the liquid 54 through the liquid line 70 and the liquid dispensing device 36, 37 are prevented. The actuating element or valve 71 is preferably arranged near the fluid-transferring interface 23 and / or the (third) coupling device 9. For actuating the actuating element 71 between the open and the closed position, a control device is provided which can be operated by the user of the medical, in particular dental, treatment device 100, 25, 1. Preferably, the control device 5 arranged in the outer housing 2 (see Figures 5, 6) controls the valve 71. According to one embodiment, control device 5 is operatively connected to the human-machine interface 26 (see Figures 1-3), such that a user of the treatment device 100, 25, 1 can operate the valve 71 via the interface 26. Alternatively, a human-machine interface 72 (see Figure 3) arranged outside and / or remote from the outer housing 2 is provided for controlling valve 71. Preferably, the interface 72 comprises a foot control, preferably a wireless foot control. Figures 16 and 17 show two alternative embodiments for conducting the liquid 54 to the liquid dispensing device 36, 37. According to Figure 16, the liquid 54 conveyed from the liquid container 11 flows at least partially or predominantly outside the outer housing 2 of the medical, in particular dental, 27 treatment device 100, 25, 1. In this case, the liquid line 70 comprises a connection tube 70A, which passes through the outer housing 2 downstream of the valve 71. The section of the liquid line 70 from the valve 71 to the connection tube 70A extends within the outer housing 2. A hose (not shown) can be coupled, for example plugged, to this connection tube 70A, said hose extending outside the outer housing 2 and through which the liquid 54 flows to the liquid dispensing device 36. The hose can also be coupled, for example plugged, to the liquid dispensing device 36, in particular an end section 70B of the liquid line 70 configured as part of the liquid dispensing device 36, such that the liquid 54 can pass from the hose into the liquid dispensing device 36. The liquid dispensing device 36 comprises a clamp 36A with which the end section 70B can be fastened to the treatment device 100, 25, 1, in particular to a handpiece or contra-angle handpiece 7. According to this embodiment, the liquid 54 is thus dispensed to the surroundings, the tool 4 and / or a treatment site also from outside the outer housing 2 and / or the handpiece or contra-angle handpiece 7. According to Figure 17, the liquid 54 conveyed from the liquid container 11 flows through the liquid dispensing device 37 within the outer housing 2 of the medical, in particular dental, treatment device 100, 25, 1 until it is dispensed into the surroundings. For this purpose, liquid line 70 extends within the outer housing 2 and in particular also within the outer sleeve 7A of the handpiece or contraangle handpiece 7 up to a bore in the outer sleeve 7A, which forms part of the liquid dispensing device 37. From this bore, liquid 54 is dispensed into the surroundings, onto the tool 4 and / or onto a treatment site. In particular, the liquid line 70 extends from valve 71 through the outer housing 2, through the first coupling device 6 for detachably coupling a dental handpiece or contra-angle handpiece 7, through the handpiece or contra-angle handpiece 7, up to the bore of the liquid dispensing device 37. At the first coupling device 6, the liquid line 70 is, according to this embodiment, divided into two sections separable from one another, one section being arranged in the handpiece or contra-angle handpiece 7 and the other section being arranged in the drive and supply unit 1 of the medical, in particular dental, treatment device 100. The separability of these two sections of the liquid line 70 in the region of the first coupling device 6 thus enables the handpiece or contra-angle handpiece 7 to be detachable from the drive and supply unit 1. Figure 18 shows an alternative embodiment of a medical, in particular dental, treatment device 100 that can be supplied with liquid from a liquid container 11 having a flexible bag 53. This treatment device 100 is configured as a cordless dental endodontic treatment device. It comprises substantially the same or similar components as the treatment devices 100, 25, 1 described above, which are provided with the same reference signs, so that reference is made to the above description in order to avoid repetition. The handpiece or contra-angle handpiece 7 of the endodontic treatment device 100 of Figure 18 is again detachably coupled to the drive and supply unit 1 via a first coupling device 6. The first coupling device 6 is provided for mechanically transmitting a rotational drive movement generated by the electric motor 3 arranged in the drive and supply unit 1 to a shaft in the handpiece or contra-angle handpiece 7 and for conducting a liquid or a cooling fluid from the drive and supply unit 1 into the handpiece or contra-angle handpiece 7. For supplying the components provided in the handpiece or contra-angle handpiece 7, for example the electric motor 3 and a display device 80, with electrical energy, a battery 10, preferably rechargeable, is again provided in the drive and supply unit 1. At an end of the endodontic treatment device 100 of Figure 18, a (third) coupling device 9 can be seen, which can be closed by a closure 35, for example a lid. As described above, a liquid container 11 with a flexible bag 53 can be detachably coupled to this (third) coupling device 9 for supplying the endodontic treatment device 100 of Figure 18 with a liquid. The structure of the liquid container 11, liquid conveyance by the pressurized gas 55 and via the liquid line 70 up to the liquid dispensing device 36, 37, the operation of the valves 57, 71 and all further features of liquid conveyance and dispensing mentioned and described above can be implemented in a corresponding manner in the endodontic treatment device 100 of Figure 18, so that reference is made to the above description in order to avoid repetition. Figure 19 shows a further embodiment of a handheld drive and supply unit 1 for implanting dental implants. In principle, the structure of the drive and supply unit 1 of Figure 19 corresponds to that of the drive and supply units 1 of Figures 1 - 7, 16 and 17 and the associated descriptions, so that, in order to avoid repetition, reference is made to the features and functions disclosed therein. Accordingly, identical components and features in Figures 1 - 7, 16, 17 and 19 are provided with identical reference signs. As can be seen from Figure 19, the handheld drive and supply unit 1 comprises an actuating element 98 that can be actuated by a user. The actuating element 98 is arranged movably, in particular rotatably, on the outer housing 2 of the drive and supply unit 1. The actuating element 98 is configured as part of the outer housing 2: when the handpiece or contra-angle handpiece 7 is separated from the drive and supply unit 1, in particular from the first coupling device 6, the actuating element 98 remains on the drive and supply unit 1. The actuating element 98 in particular comprises a rotary ring 98A that is rotatable about the central axis 28 of the coupling pin 24 and / or of the transmission 31, 76. As will be described in detail below, an adjusting device 77 provided in the outer housing 2 can be actuated or set by a user by the actuating element 98 in order to be able to select different transmission ratios, such that the handpiece or contra-angle handpiece 7 coupled to the first coupling device 6 can be operated with different rotational speeds and / or torques. Figures 20 and 21 show a sectional view through the first coupling device 6 provided on the outer housing 2, the actuating element 98, 98A, the adjusting device 77 for setting different transmission ratios, and the transmission or gear unit 31 comprising a planetary transmission 76, wherein the adjusting device 77 assumes different positions in the two figures, such that in Figure 20 the rotational drive movement generated by the electric motor 3 (see Figures 5, 6) is transmitted directly (i.e. not via the transmission 31, 76) to the handpiece or contra-angle handpiece 7 (transmission ratio 1:1), while in Figure 21 the rotational drive movement generated by the electric motor 3 is transmitted to the handpiece or contra-angle handpiece via the transmission 31, 76. In Figure 21, the transmission ratio is thus not equal to 1:1, in particular a reduction is effected by the planetary transmission 76. In Figures 20 and 21, a drive train or shaft train 79 arranged in the outer housing 2 can be seen, which connects the electric motor 3 to the first coupling device 6 or extends between the electric motor 3 and the first coupling device 6 in order to transmit the rotational drive movement of the electric motor 3 to the handpiece or contra-angle handpiece 7. The shaft train 79 comprises at least one shaft, preferably a plurality of shafts or shaft sections 78, 78A, 78B, which are coupled and / or can be coupled to one another in a torque-transmitting manner. One end of the shaft train 79 or of a shaft 78B extends 29 into the coupling pin 24 in order to be connectable to a shaft arranged in the handpiece or contra-angle handpiece 7. As can be seen from Figures 20 and 21, the shaft 78 is configured to be movable, preferably displaceable, or slidable, in particular axially displaceable, or slidable with respect to the central axis 28. The shaft 78 is axially displaceable relative to the transmission 31, 76 and to the other shafts 78A, 78B of the shaft train 79. The transmission or gear unit 31 comprises a planetary transmission 76 or is configured as a planetary transmission 76. According to Figures 20 - 23, the planetary transmission 76 is configured as a gear planetary transmission; however, alternatively it may also comprise a ball planetary transmission. Since the structure and function of a planetary transmission 76 are familiar to a person skilled in the art, they will not be discussed in detail. As can be seen in particular from Figures 20 and 21, the central rolling body or sun gear 90 is arranged on the shaft train 79, in particular on shaft 78A. The shaft 78A and the sun gear 90 are set into rotation by the electric motor 3. The central rolling body 90 is engaged with a plurality of circumferential rolling bodies or planet gears 91B, for example two. The planet gears 91B are arranged rotatably on a rotating carrier 91, which in particular comprises a hollow shaft 91A. The planet gears 91B mesh with a ring gear 92. The ring gear 92 (see Figure 23) is fixedly connected to the outer housing 2. The planetary transmission 76 is configured as a reduction transmission, i.e., as a transmission that reduces the rotational speed of the rotational drive movement received from the electric motor 3 and in particular increases the torque of the rotational drive movement received from the electric motor 3. The shaft train 79, in particular the displaceable or slidable shaft 78, extends through the hollow carrier 91, 91A. The displaceable shaft 78 is arranged displaceably inside the hollow shaft 91A and / or relative to the hollow carrier 91, 91A. Furthermore, a bushing 87 is provided inside the rotating hollow carrier 91, in particular in the hollow shaft 91A (see Figures 21, 22, 25), which bushing is connected rotationally fixed to the hollow shaft 91A and rotates together with the hollow carrier 91, 91A at the rotational speed changed by the transmission 31, 76. The bushing 87 has a substantially cylindrical or hollow-cylindrical shape. The shaft train 79, in particular the displaceable or slidable shaft 78, extends through the hollow-cylindrical bushing 87. The displaceable or slidable shaft 78 is arranged displaceably inside the bushing 87 and / or relative to the bushing 87. The adjusting device 77 is configured such that it selectively, for setting a (first) transmission ratio, couples the shaft 78 to the transmission 31, 76, such that a rotational drive movement having the rotational speed changed by the transmission 31, 76 is transmittable via the shafts 78, 78B and the first coupling device 6 to the dental handpiece or contra-angle handpiece 7 (reduction, see Figure 21), or, for setting a further (second) transmission ratio, decouples the shaft 78 and the transmission 31, 76, such that the rotational drive movement having the rotational speed generated by the electric motor 3 is transmittable via the shafts 78, 78B and the first coupling device 6 to the dental handpiece or contraangle handpiece 7 (transmission ratio 1:1, see Figure 20). For selectively setting the different transmission ratios, the movable, displaceable or slidable shaft 78 is displaceable by the adjusting device 77. For setting the reduction transmission ratio (reduction) according to Figure 21, the displaceable or slidable shaft 78, and thus also the shaft 78B, is connected to the transmission 31, 76 via the bushing 87 in a torque-transmitting manner, and the direct, immediate coupling and / or contact between the shaft 78 and the shaft 78A is released. The rotational 30 drive movement and / or the torque is / are thus transmitted from the shaft 78A via the transmission 31, 76, the bushing 87 and the shafts 78, 78B to the handpiece or contra-angle handpiece 7. For setting the transmission ratio 1:1 according to Figure 20, the shaft 78 and the transmission 31, 76 can be decoupled from one another by the adjusting device 77. By displacing the shaft 78 the contact between the bushing 87 and the shaft 78 is released and the shaft 78 and the shaft 78A are directly coupled to one another and / or a direct contact is established between the shaft 78 and the shaft 78A. The rotational drive movement and / or the torque is / are thus transmitted from the shaft train 79 while bypassing the transmission 31, 76 and / or directly from the shaft 78A to the shafts 78, 78B and further to the handpiece or contra-angle handpiece 7. As can be seen from Figure 20, at the transmission ratio 1:1 the sun gear 90 and the entire transmission 31, 76 are also driven, however, since the coupling between the bushing 87 and the shaft 78 is cancelled, the transmission 31, 76 or the bushing 87 does not transmit any rotational movement to the shaft 78. Thus, a possibility is created to set different transmission ratios without having to axially displace, with respect to the central axis 28, the planetary transmission 76, in particular its components, such as for example the sun gear 90, the planet carrier 91 with the planet gears 91B and / or the ring gear 92. The planetary transmission 76 is thus arranged immovably in the outer housing 2. The selective coupling between the shaft 78 and the bushing 87 or the shafts 78, 78A is effected by driver elements 81, 83 and counter-driver elements 82, 84. The shaft 78 comprises a first driver element 81, which according to the embodiment of Figures 20, 21 is configured as a groove or pin receptacle 81A (see in particular Figure 21), and a second driver element 83, which according to the embodiment of Figures 20, 21 is configured as a pin 83A. The shaft 78 and the first and second driver elements 81, 83 are fixedly connected to one another and / or jointly movable by the adjusting device 77. The pin 83A is, for example, press-fitted into openings 103 in the shaft 78 (see Figure 24). The first counter-driver element 82 is provided on the shaft 78A and is configured as a pin 82A according to the embodiment of Figures 20, 21. The shaft 78A and the counter-driver element 82 are fixedly connected to one another and / or can be set into rotation jointly. The pin 82A is, for example, press-fitted into openings in the shaft 78A. The second counter-driver element 84 is provided on the bushing 87 and is configured as a groove or pin receptacle 84A according to the embodiment of Figures 20, 21 (see in particular Figure 20). By displacing the shaft 78 and by the joint movement of shaft 78, first driver element and second driver element 81, 83, either the elements 81, 82 couple, in that the pin 82A of the shaft 78A engages in the pin receptacle 81A of the shaft 78 (see Figure 20), or the elements 83, 84 couple, in that the pin 83A of the shaft 78 engages in the pin receptacle 84A of the bushing 87 (see Figure 21), so that, as described above, the different transmission ratios can be set. In Figure 24, the shaft 78 and the first driver element 81 with the pin receptacle 81A are shown enlarged. Figure 25 shows the bushing 87 and the second counter-driver element 84 with the pin receptacle 84A. Both pin receptacles 81A, 84A each comprise a recess 85, which is provided in an end face 86 of the shaft 78 or of the cylindrical bushing 87. The recess 85 extends over the entire diameter of the shaft 78 or bushing 87 orthogonally to a central axis of the shaft 78 or bushing 87 and preferably intersects the central axis. The end face 86 is divided into two halves by the recess 85, wherein each half of the end face 86 comprises an apex 88 from which inclined planes 89 extend toward the pin receptacles 81A, 84A. If the shaft 78 is coupled to the bushing 87 or the shaft 78A without the pins 82A, 31 83A immediately engaging in the pin receptacles 81A, 84A, the pins 82A, 83A strike the inclined planes 89 and subsequently slide on the inclined planes 89 into the recess 85, whereby smooth engagement of the pins 82A, 83A into the recess 85 is achieved. The adjusting device 77 comprises a cam device 93, which comprises a cam groove 94, a cam follower 95 and a control disc 96 having a control track 96A provided on the circumference of the control disc 96. The cam groove 94 is provided in a rotationally fixed inner sleeve 97. As can be seen in particular from Figures 22 and 23, the rotationally fixed inner sleeve 97 is configured in one piece with the (cylindrical) coupling pin 24. Via a step or shoulder 104, the coupling pin 24 is connected to a central sleeve section 97A, the outer diameter of which is greater than that of the coupling pin 24. At the end of the central sleeve section 97A that is remote from the coupling pin 24, an annular flange 97B adjoins, the outer diameter of which is greater than that of the central sleeve section 97A. While the coupling pin 24 projects beyond the outer housing 2, in particular the actuating element 98, 98A of the drive and supply unit 1, at least a part of the central sleeve section 97A and the flange 97B are covered by the outer housing 2, in particular the actuating element 98, and / or received in the outer housing 2. The cam groove 94 is arranged in the central sleeve section 97A and / or spaced apart from the coupling pin 24. The cam groove 94 extends radially about the central axis 28 of the transmission 31, 76 and / or of the coupling pin 24. The cam groove 94 extends obliquely offset along the central axis 28 such that one end of the cam groove 94 is closer to the flange 97B or transmission 31, 76 and another end of the cam groove 94 is closer to the coupling pin 24. It can be seen from Figure 22 that preferably two mutually spaced apart cam grooves 94, in particular opposite one another, are provided on the rotationally fixed inner sleeve 97. Correspondingly, two cam followers 95 and two control tracks 96A provided on the circumference of the control disc 96 are provided, whereby the operability of the cam device 93 becomes more stable and reliable. The control disc 96 is operatively connected to the shaft 78 (see Figures 20, 21). For this purpose, the control disc 96 comprises a bore 99 in which the shaft 78 is received. A rolling bearing 101, in particular a ball bearing, is also arranged in the bore 99, which rotatably supports the shaft 78 in the control disc 96. The control disc 96, the shaft 78 and the rolling bearing 101 are connected to one another such that they are jointly movable, in particular displaceable or slidable, axially along the central axis 28. By providing the rolling bearing, the shaft 78 is rotatably supported in the bore 99 of the control disc 96 and / or is rotatable relative to the control disc 96. The control disc 96 is arranged fixed against rotation in the outer housing 2 and / or relative to the outer housing. A control track 96A, preferably two control tracks 96A, is provided on the outer circumference of the control disc 96 (see Figure 23). The two control tracks 96A are spaced apart from one another, in particular opposite one another. A cam follower 95 is displaceably received in each control track 96A. According to the embodiments of Figures 20 - 23, the at least one cam follower 95 is configured as a rotationally symmetrical body, in particular as a ball. The cam followers 95 extend from the actuating element 98, 98A through the cam groove 94 into the respective control track 96A. By actuation of the actuating element 98, in particular rotation of the rotary ring 98A, the at least one cam follower 95 can be guided in the cam groove 94 along the central axis 28. In order that the at least one cam follower 95 is entrained by the actuating element 98 when the actuating element 98 is actuated, an elongated groove 32 or notch 105 extending along the central axis 28 is provided on the inside of the actuating element 98 (see Figure 22), in which part of the at least one cam follower 95 is received and / or guided. During its movement along the central axis 28, the at least one cam follower 95 entrains the control disc 96 and the shaft 78 connected thereto with the pin 83A and the pin receptacle 81A, so that these are likewise axially displaced and the respective driver elements 81, 83 and counter-driver elements 82, 84 engage one another for setting the different transmission ratios, as described above. In order to fix a transmission ratio set by a user via the adjusting device 77 and / or the position of the adjusting device and / or the shaft 78, a detent device 102 is provided (see Figures 22 and 23). The detent device 102 is provided between the actuating element 98, 98A and the rotationally fixed inner sleeve 97. The detent device 102 comprises a detent body 102A biased by a spring element, for example a ball, and a detent recess 102B into which the detent body 102A engages. According to Figures 22, 23, the spring element and the detent body 102A are arranged in the movable actuating element 98, in particular the rotary ring 98A, in a bore of a wall of the actuating element 98, 98A. The detent recess 102B is accordingly provided on the rotationally fixed inner sleeve 97, for example in the flange 97B. The detent recess 102B in particular comprises a groove 106 in the flange 97B, wherein depressions are provided at both ends of the groove 106. As can be seen from Figures 20 and 21, the actuating element 98, 98A and the flange 97B adjoin one another and / or the actuating element 98, 98A moves along the flange 97B such that the detent body 102A engages in the groove 106 and such that, when one of the different transmission ratios is set, the detent body 102A latches into one of the depressions at the end of the groove 106. By this latching, the user also receives haptic and / or acoustic feedback that one of the transmission ratios has been set. The described or illustrated embodiments serve in particular to illustrate the invention. The features disclosed in one embodiment are therefore not limited to this embodiment but can be combined individually or jointly with one or more features of one of the other embodiments.

Claims

1. Handheld drive and supply unit (1) for implanting dental implants having an outer housing (2), which separates the drive and supply unit (1) from the surroundings, comprising:an electric motor (3) arranged in the outer housing (2) for the rotational drive of a dental tool (4), a control device (5) arranged in the outer housing (2) for controlling the drive and supply unit (1), a first coupling device (6) provided on the outer housing (2) for releasably coupling a dental handpiece or contra-angle handpiece (7) to the drive and supply unit (1), for mechanically transmitting a rotational drive movement generated by the electric motor (3) to a shaft in the handpiece or contra-angle handpiece (7), and for conducting a cooling fluid from the drive and supply unit (1) into the handpiece or contra-angle handpiece (7),a second coupling device (8) provided on or in the outer housing (2) for releasably coupling a battery (10) for supplying the electric motor (3) with electrical energy,a third coupling device (9) provided on or in the outer housing (2) for releasably coupling a cooling fluid container (11), characterized bya transmission (31, 76) arranged in the outer housing (2), which is operatively connected to the electric motor (3) in order to receive the rotational drive movement generated by the electric motor (3) and to change the rotational speed and / or the torque of the received rotational drive movement,a shaft (78) arranged in the outer housing (2), which is operatively connected to the electric motor (3) in order to transmit the rotational drive movement generated by the electric motor (3) via the first coupling device (6) to the dental handpiece or contra-angle handpiece (7), andan adjusting device (77) arranged in the outer housing (2) for setting different transmission ratios, wherein the adjusting device (77) is configured such that it selectivelyfor setting a first transmission ratio couples the shaft (78) to the transmission (31, 76), such that a rotational drive movement having the rotational speed changed by the transmission (31, 76) is transmitted via the shaft (78) and the first coupling device (6) to the dental handpiece or contraangle handpiece (7), orfor setting a second transmission ratio decouples the shaft (78) and the transmission (31, 76), such that the rotational drive movement having the rotational speed generated by the electric motor (3) is transmitted via the shaft (78) and the first coupling device (6) to the dental handpiece or contra-angle handpiece (7).

2. Handheld drive and supply unit (1) according to claim 1, characterized in that the shaft (78) is slidable relative to the transmission (31, 76).

3. Handheld drive and supply unit (1) according to claim 1 or 2, characterized in thatthe shaft (78) is part of a shaft train (79) which connects the electric motor (3) to the dental handpiece or contra-angle handpiece (7) via the first coupling device (6) for transmitting the rotational drive movement generated by the electric motor (3).

4. Handheld drive and supply unit (1) according to one of the preceding claims, characterized in thatthe shaft (78) comprises a first driving element (81) and a second driving element (83), wherein the shaft (78) and the first and second driving elements (81, 83) are jointly movable by the adjusting device (77).

5. Handheld drive and supply unit (1) according to claim 4, characterized in thatthrough the joint movement of the shaft (78), the first and second driving elements (81, 83), selectively the first driving element (81) couples with a first counter-driving element (82) or the second driving element (83) couples with a second counter-driving element (84), such that the different transmission ratios can be set.

6. Handheld drive and supply unit (1) according to claim 5, characterized in thatthe first driving element (81) and first counter-driving element (82) and / or the second driving element (83) and second counter-driving element (84) each comprise a pin (82A, 83A) and a pin receptacle (81A, 84A).

7. Handheld drive and supply unit (1) according to claim 6, characterized in thatthe pin receptacle (81A, 84A) comprises a recess (85) which is provided in an end face (86) of the shaft (78) or of a cylindrical bushing (87) connected to the transmission (31, 76), wherein the end face (86) comprises an apex (88), from which an inclined plane (89) extends toward the pin receptacle (81A, 84A), such that the pin (82A, 83A) slides on the inclined plane (89) into the recess (85) for coupling into the recess (85).

8. Handheld drive and supply unit (1) according to one of the preceding claims, characterized in that the transmission (31, 76) comprises a planetary transmission (76).

9. Handheld drive and supply unit (1) according to claim 8, characterized in thatthe planetary transmission (76), in particular the components of the planetary transmission (76), for example the sun gear (90), the planet carrier (91) with the planet gears (91B) and the ring gear (92), is / are arranged axially immovably in the outer housing (2) with respect to the central axis (28) of the coupling pin (24) and / or of the electric motor (3).

10. Handheld drive and supply unit (1) according to one of the preceding claims, characterized in thatthe adjusting device (77) comprises a cam device (93), which comprises a cam groove (94), a cam follower (95) and a control disc (96) having a control track (96A) provided on the circumference of the control disc (96).

11. Handheld drive and supply unit (1) according to claim 10, characterized in thatthe cam groove (94) is provided in a rotationally fixed inner sleeve (97), wherein the cam groove (94) extends radially around the central axis (28) and obliquely offset along the central axis (28).

12. Handheld drive and supply unit (1) according to claim 10 or 11, characterized in thatthe control disc (96) is operatively connected to the shaft (78), and the cam follower (95) extends from an actuating element through the cam groove into the control track (96A), such that by actuation of the actuating element (98), the cam follower (95) can be guided in the cam groove (94) along the central axis (28), so that the control disc (96) and the shaft (78) connected thereto are axially slidable along the central axis (28) for setting the different transmission ratios.

13. Handheld drive and supply unit (1) according to one of claims 10 - 12, characterized in thatthe control disc (96) comprises a bore (99), in which the shaft (78) and a rolling bearing (101) are received, such that the rolling bearing (101) rotatably supports the shaft (78) in the control disc (96).

14. Handheld drive and supply unit (1) according to one of the preceding claims, characterized in thatthe adjusting device (77) is adjustable via an actuating element (98) that can be actuated by a user, wherein the actuating element (98) is arranged movably on the outer housing (2) of the drive and supply unit (1), and wherein the actuating element (98) preferably comprises a rotary ring (98A) or a slider, which is rotatable about the central axis (28) of the coupling pin (24) and / or of the electric motor (3).

15. Handheld drive and supply unit (1) according to one of claims 12 - 14, characterized bya detent device (102) provided between the actuating element (98) that can be actuated by the user and the rotationally fixed inner sleeve (97), wherein the detent device (102) is configured to fix the actuating element (98) in a position in which one of the different transmission ratios has been set.

16. A medical, in particular dental, treatment device (100, 25, 1), comprising:an outer housing (2), which separates the medical, in particular dental, treatment device (1) from the surroundings,a drive device (3) arranged in the outer housing (2) for driving a tool (4) connectable to the medical, in particular dental, treatment device,a control device (5) arranged in the outer housing (2) for controlling the medical, in particular dental, treatment device (1),a liquid dispensing device (36, 37), which is configured for dispensing a liquid (54) from the medical, in particular dental, treatment device (100, 25, 1) into the surroundings, anda liquid container (11), which contains the liquid dispensable by the liquid dispensing device (36, 37) and can be detachably coupled to a coupling device (9) provided on or in the outer housing (2), wherein the liquid container (11) comprises an outer wall (51) which separates an interior container space (52) of the liquid container (11) from the surroundings, characterized in that the liquid container (11) further comprises:a flexible bag (53) received in the interior container space (52), having a bag volume (56) in which the liquid (54) is received,a pressurized gas (55), which is provided in the interior container space (52), but outside the bag volume (56), anda valve (57) with a valve tube (58), which is in fluid communication with the bag volume (56), wherein the valve (57) is switchable between a closed position, in which the liquid (54) received in the bag volume (56) cannot escape from the flexible bag (53), and an open position, in which the liquid (54) received in the bag volume (56) can escape from the flexible bag (53) through the valve tube (58), wherein, in the open position, the pressure exerted by the pressurized gas (55) on the flexible bag (53) drives the liquid (54) from the flexible bag (53) into the valve tube (58), anda connector (60), which connects the liquid container (11) to the medical, in particular dental, treatment device (100, 25, 1) in such a manner that the liquid (54) can be conveyed from the flexible bag (53) and through the valve tube (58) into a liquid line (70) of the medical, in particular dental, treatment device (100, 25, 1).

17. Medical, in particular dental, treatment device (100, 25, 1) according to claim 16, characterized byan actuating element (71) provided in the outer housing (2) of the medical, in particular dental, treatment device (100, 25, 1), which controls the dispensing of the liquid (54).

18. Medical, in particular dental, treatment device (100, 25, 1) according to claim 17, characterized in thatthe actuating element (71) is controllable by the control device (5) arranged in the outer housing (2) and through a human-machine interface (26) provided on the medical, in particular dental, treatment device (100, 25, 1), or an interface (72) arranged remotely from the outer housing (2), for example by means of a foot control.

19. Medical, in particular dental, treatment device (100, 25, 1) according to one of the preceding claims 16-18, characterized in thatthe connector (60) comprises a connector body (61) which provides a first connection element (62) for connecting the connector (60) to the outer wall (51) of the liquid container (11) and a second connection element (63) for connecting to the medical, in particular dental, treatment device (100, 25, 1).

20. Medical, in particular dental, treatment device (100, 25, 1) according to claim 19, characterized in thatno actuating element for actuating the valve (57) of the liquid container (11) between the closed position and the open position is provided on the connector body (61).

21. Medical, in particular dental, treatment device (100, 25, 1) according to one of the preceding claims 16-20, characterized in thatthe liquid container (11) does not have a finger push button or finger rotary knob for actuating the valve (57) of the liquid container (11) between the closed position and the open position.

22. Medical, in particular dental, treatment device (100, 25, 1) according to one of the preceding claims 16-21, characterized in thatthe connector (60) is arranged at an end of the liquid container (11) at which the valve (57) of the liquid container (11) is provided, wherein, in particular, the connector body (61) comprises a passage (64) into which the valve tube (58) and / or a liquid line (70) of the medical, in particular dental, treatment device (100, 25, 1) extends.

23. Medical, in particular dental, treatment device (100, 25, 1) according to one of the preceding claims 16-22, characterized in thatthe medical, in particular dental, treatment device (100, 25, 1) is configured as a cordless treatment device without a line connection to an energy and fluid source arranged outside the outer housing (2), in particular as a cordless drive and supply unit (1) for implanting dental implants.

24. Liquid container (11), which can be coupled to a medical, in particular dental, treatment device (100, 25, 1) in order to dispense a liquid (54) contained in the liquid container (11) to the medical, in particular dental, treatment device (100, 25, 1), wherein the liquid container (11) comprises: an outer wall (51), which separates an interior container space (52) of the liquid container (11) from the surroundings, and is characterized bya flexible bag (53) received in the interior container space (52) and having a bag volume (56), in which the liquid (54) to be dispensed to the medical, in particular dental, treatment device (100, 25, 1) can be received,a pressurized gas (55), which is provided in the interior container space (52), but outside the bag volume (56), anda valve (57) with a valve tube (58), which is in fluid communication with the bag volume (56), wherein the valve (57) is switchable between a closed position, in which the liquid (54) received in the bag volume (56) cannot escape from the flexible bag (53), and an open position, in which the liquid (54) received in the bag volume (56) can escape from the flexible bag (53) through the valve tube (58), wherein, in the open position, the pressure exerted by the pressurized gas (55) on the flexible bag (53) drives the liquid (54) from the flexible bag (53) into the valve tube (58), a connector (60), which connects the liquid container (11) to the medical, in particular dental, treatment device (100, 25, 1) in such a manner that the liquid (54) can be conveyed from the flexible bag (53) and through the valve tube (58) into a liquid line (70) of the medical, in particular dental, treatment device (100, 25, 1), wherein the connector (60) comprises a connector body (61), on which a first connection element (62) for connecting the connector (60) to the outer wall (51) of the liquid container (11) and a second connection element (63) for connecting to the medical, in particular dental, treatment device (100, 25, 1) are provided, wherein no actuating element for actuating the valve (57) between the closed position and the open position is provided on the connector body (61).

25. Liquid container (11) according to claim 24, characterized bya mechanical and / or magnetic second connection element (63).

26. Liquid container (11) according to claim 24 or 25, characterized in thatthe liquid container (11) does not have a finger push button or finger rotary knob for actuating the valve (57) between the closed position and the open position.

27. Liquid container (11) according to one of the preceding claims 24-26, characterized in that the connector (60) is arranged at an end of the liquid container (11) at which the valve (57) of the liquid container (11) is provided.

28. Liquid container (11) according to claim 27, characterized in thatthe connector body (61) comprises a passage (64), into which the valve tube (58) and / or a liquid line (70) of the medical, in particular dental, treatment device (100, 25, 1) extends.

29. Liquid container (11) according to one of the preceding claims 24-28, characterized in that the liquid (54) comprises water, an aqueous solution, for example a saline solution, an anesthetic, a medicinal active substance, and / or an indicator liquid.

30. Use of a liquid container (11), the liquid container (11) comprising:an outer wall (51), which separates an interior container space (52) of the liquid container (11) from the surroundings,a flexible bag (53) arranged in the interior container space (52) and having a bag volume (56), in which a liquid (54) is received,a pressurized gas (55), which is provided in the interior container space (52), but outside the bag volume (56), anda valve (57) with a valve tube (58), which is in fluid communication with the bag volume (56), wherein the valve (57) is switchable between a closed position, in which the liquid (55) received in the bag volume (56) cannot escape from the flexible bag (53), and an open position, in which the liquid (54) received in the bag volume (56) can escape from the flexible bag (53) through the valve tube (58), wherein, in the open position, the pressure exerted by the pressurized gas (55) on the flexible bag (53) drives the liquid (54) from the flexible bag (53) into the valve tube (58), anda connector (60), which connects the liquid container (11) to a medical, in particular dental, treatment device (100, 25, 1) in such a manner that the liquid (54) can be conveyed from the flexible bag (53) and through the valve tube (58) into a liquid line (70) of the medical, in particular dental, treatment device (100, 25, 1),in particular use of a liquid container (11) according to one of the preceding claims 24-29, as a liquid source of a medical, in particular dental, treatment device (100, 25, 1).

31. Handheld drive and supply unit (1) for implanting dental implants having an outer housing (2), which separates the drive and supply unit (1) from the surroundings, characterized by:an electric motor (3) arranged in the outer housing (2) for the rotational drive of a dental tool (4), a control device (5) arranged in the outer housing (2) for controlling the drive and supply unit (1), a first coupling device (6) provided on the outer housing (2) for releasably coupling a dental handpiece or contra-angle handpiece (7) to the drive and supply unit (1), for mechanically transmitting a rotational drive movement generated by the electric motor (3) to a shaft in the handpiece or contra-angle handpiece (7), and for conducting a liquid or a cooling fluid from the drive and supply unit (1) into the handpiece or contra-angle handpiece (7),a second coupling device (8) provided on or in the outer housing (2) for releasably coupling a battery (10) for supplying the electric motor (3) with electrical energy, anda third coupling device (9) provided on or in the outer housing (2) for releasably coupling a liquid container or cooling fluid container (11),wherein the first, second and third coupling devices (6, 8, 9) are independent coupling devices separate from one another, and whereina liquid container (11) can be coupled or is coupled to the third coupling device (9), the liquid container comprising:an outer wall (51), which separates a container interior (52) of the liquid container (11) from the surroundings,a flexible bag (53) arranged in the container interior (52) having a bag volume (56), in which a liquid (54) is received,a pressurized gas (55), which is provided in the container interior (52), but outside the bag volume (56), anda valve (57) having a valve tube (58), which is in fluid communication with the bag volume (56), wherein the valve (57) is switchable between a closed position, in which the liquid (54) received in the bag volume (56) cannot escape from the flexible bag (53), and an open position, in which the liquid (54) received in the bag volume (56) can escape from the flexible bag (53) through the valve tube (58), wherein in the open position the pressure exerted by the pressurized gas (55) on the flexible bag (53) drives the liquid (54) out of the flexible bag (53) into the valve tube (58), and a connector (60), which connects the liquid container (11) to the drive and supply unit (1) such that the liquid (54) is conveyable from the flexible bag (53) and through the valve tube (58) into a liquid line (70) of the drive and supply unit (1).

32. Handheld drive and supply unit (1) according to claim 31, characterized in thatthe first coupling device (6) for releasably coupling a dental handpiece or contra-angle handpiece (7) and at least the second coupling device (8) or the third coupling device (9), preferably the second coupling device (8) for releasably coupling a battery (10), are arranged at opposite ends (2C, 2D) of the drive and supply unit (1).

33. Handheld drive and supply unit (1) according to claim 32, characterized in thatthe first coupling device (6) for releasably coupling a dental handpiece or contra-angle handpiece (7) and optionally the second coupling device (8) or the third coupling device (9), preferably the second coupling device (8) for releasably coupling a battery (10), are arranged in a sectional plane (14) through the drive and supply unit (1), which extends through the opposite ends (2C, 2D) of the drive and supply unit (1).

34. Handheld drive and supply unit (1) according to claim 33, characterized in thatthe other coupling device of the second or third coupling device (8, 9), preferably the third coupling device (9) for releasably coupling a liquid container or cooling fluid container (11), is arranged offset from and / or outside the sectional plane (14).

35. Handheld drive and supply unit (1) according to claim 34, characterized in thatthe second or third coupling device (8, 9) arranged offset from and / or outside the sectional plane (14) is provided between the two coupling devices (6, 9; 6, 8) arranged in the sectional plane (14).

36. Handheld drive and supply unit (1) according to one of the preceding claims 31 - 35, characterized bya central plane (15) extending through the drive and supply unit (1), wherein the first coupling device (6) is arranged on a first side (16) of the central plane (15), and the second and third coupling devices (8, 9) are arranged on another, second side (17) of the central plane (15).

37. Handheld drive and supply unit (1) according to one of the preceding claims 31 - 36, characterized in thatthe electric motor (3) is arranged adjoining the first coupling device (6) and / or aligned with the first coupling device (6).

38. Handheld drive and supply unit (1) according to claim 36 or 37, characterized in thatthe electric motor (3) together with the first coupling device (6) is arranged on the first side (16) of the central plane (15).

39. Handheld drive and supply unit (1) according to claim 36, 37 or 38, characterized in thatthe electric motor (3) is arranged with respect to the second coupling device (8) and / or a battery (10) connected to the second coupling device (8) such that the central plane (15) extends between the electric motor (3) and the second coupling device (8) and / or the battery (10) connected to the second coupling device (8).

40. Handheld drive and supply unit (1) according to one of the preceding claims 31 - 39, characterized in thatthe control device (5) for controlling the drive and supply unit (1) comprises a circuit board (18), which is arranged between the electric motor (3) and the second coupling device (8) and / or a battery (10) connected to the second coupling device (8).

41. Handheld drive and supply unit (1) according to one of the preceding claims 31 - 40, characterized in thatthe second coupling device (8) comprises an opening (19) and a, preferably cylindrical, receptacle (20), into which the battery (10) can be inserted.

42. Handheld drive and supply unit (1) according to one of the preceding claims 31 - 41, characterized in thatthe third coupling device (9) comprises an opening (21) and a preferably cylindrical receptacle (22), into which the liquid container or cooling fluid container (11) can be inserted.

43. Handheld drive and supply unit (1) according to one of the preceding claims 31 - 42, characterized in thatthe third coupling device (9) comprises a fluid-transmitting interface (23) for connection to a liquid container or cooling fluid container (11), via which liquid (54) from the liquid container (11) or cooling fluid from the cooling fluid container (11) can be transferred into the drive and supply unit (1).

44. Handheld drive and supply unit (1) according to one of the preceding claims 31 - 43, characterized in thatthe first coupling device (6) comprises a coupling pin (24), onto which the handpiece or contraangle handpiece (7) can be mounted in a fluid-transmitting and drive-force-transmitting manner.

45. Dental implantation device (25), characterized bya handheld drive and supply unit (1) according to one of the preceding claims 31 - 44, a handpiece or contra-angle handpiece (7), a battery (10), and a liquid container or cooling fluid container (11).

46. Handheld drive and supply unit (1) for implanting dental implants having an outer housing (2), which separates the drive and supply unit (1) from the surroundings, characterized by:an electric motor (3) arranged in the outer housing (2) for the rotational drive of a dental tool (4), a control device (5) arranged in the outer housing (2) for controlling the drive and supply unit (1), a first coupling device (6) provided on the outer housing (2) for releasably coupling a dental handpiece or contra-angle handpiece (7) to the drive and supply unit (1), for mechanically transmitting a rotational drive movement generated by the electric motor (3) to a shaft in the handpiece or contra-angle handpiece (7), and for conducting a cooling fluid from the drive and supply unit (1) into the handpiece or contra-angle handpiece (7),a second coupling device (8) provided on or in the outer housing (2) for releasably coupling a battery (10) for supplying the electric motor (3) with electrical energy, anda third coupling device (9) provided on or in the outer housing (2) for releasably coupling a cooling fluid container (11),wherein the first, second and third coupling devices (6, 8, 9) are independent coupling devices separate from one another.

47. Handheld drive and supply unit (1) according to claim 46, characterized in thatthe first coupling device (6) for releasably coupling a dental handpiece or contra-angle handpiece (7) and at least the second coupling device (8) or the third coupling device (9), preferably the second coupling device (8) for releasably coupling a battery (10), are arranged at opposite ends (2C, 2D) of the drive and supply unit (1).

48. Handheld drive and supply unit (1) according to claim 47, characterized in thatthe first coupling device (6) for releasably coupling a dental handpiece or contra-angle handpiece (7) and optionally the second coupling device (8) or the third coupling device (9), preferably the second coupling device (8) for releasably coupling a battery (10), are arranged in a sectional plane (14) through the drive and supply unit (1), which extends through the opposite ends (2C, 2D) of the drive and supply unit (1).

49. Handheld drive and supply unit (1) according to claim 48, characterized in thatthe other coupling device of the second or third coupling device (8, 9), preferably the third coupling device (9) for releasably coupling a cooling fluid container (11), is arranged offset from and / or outside the sectional plane (14).

50. Handheld drive and supply unit (1) according to claim 49, characterized in thatthe second or third coupling device (8, 9) arranged offset from and / or outside the sectional plane (14) is provided between the two coupling devices (6, 9; 6, 8) arranged in the sectional plane (14).

51. Handheld drive and supply unit (1) according to one of the preceding claims 46 - 50, characterized bya central plane (15) extending through the drive and supply unit (1), wherein the first coupling device (6) is arranged on a first side (16) of the central plane (15), and the second and third coupling devices (8, 9) are arranged on another, second side (17) of the central plane (15).

52. Handheld drive and supply unit (1) according to one of the preceding claims 46 - 51, characterized in thatthe electric motor (3) is arranged adjoining the first coupling device (6) and / or aligned with the first coupling device (6).

53. Handheld drive and supply unit (1) according to claim 51 or 52, characterized in thatthe electric motor (3) together with the first coupling device (6) is arranged on the first side (16) of the central plane (15).

54. Handheld drive and supply unit (1) according to claim 51, 52 or 53, characterized in that the electric motor (3) is arranged with respect to the second coupling device (8) and / or a battery (10) connected to the second coupling device (8) such that the central plane (15) extends between the electric motor (3) and the second coupling device (8) and / or the battery (10) connected to the second coupling device (8).

55. Handheld drive and supply unit (1) according to one of the preceding claims 46 - 54, characterized in thatthe control device (5) for controlling the drive and supply unit (1) comprises a circuit board (18), which is arranged between the electric motor (3) and the second coupling device (8) and / or a battery (10) connected to the second coupling device (8).

56. Handheld drive and supply unit (1) according to one of the preceding claims 46 - 55, characterized in thatthe second coupling device (8) comprises an opening (19) and a preferably cylindrical receptacle (20), into which the battery (10) can be inserted.

57. Handheld drive and supply unit (1) according to one of the preceding claims 46 - 56, characterized in thatthe third coupling device (9) comprises an opening (21) and a preferably cylindrical receptacle (22), into which the cooling fluid container (11) can be inserted.

58. Handheld drive and supply unit (1) according to one of the preceding claims 46 - 57, characterized in thatthe third coupling device (9) comprises a fluid-transmitting interface (23) for connection to a cooling fluid container (11), via which cooling fluid can be transferred from the cooling fluid container (11) into the drive and supply unit (1).

59. Handheld drive and supply unit (1) according to one of the preceding claims 46 - 58, characterized in thatthe first coupling device (6) comprises a coupling pin (24), onto which the handpiece or contraangle handpiece (7) can be mounted in a fluid-transmitting and drive-force-transmitting manner.

60. Dental implantation device (25), characterized bya handheld drive and supply unit (1) according to one of the preceding claims 46 - 59, a handpiece or contra-angle handpiece (7), a battery (10), and a cooling fluid container (11).

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