DE2154650A1 - Medical device - Google Patents

Description

DR. ING. E. HOFFMANN · DIPL. ING. W. EITLE DR. RER. NAT. K. HOFFMANN

PATENT Attorneys λ λ _r / λ _{r Λ}

D-8000 MÖNCHEN 81ARABEUASTRASSE 4 TELEPHONE (0811) 911087

Electro-Dent Inc., Cherry Hill, N.J./USA

Medical device

The invention relates to a medical device for touching an area on the body of a Patients, namely dental and medical tools that cause pain, in particular devices to relieve pain caused by the use of such tools through a form of electrical desensitization, which is carried out by the tool directly at the point of contact with the patient will.

Heretofore, electrical analgesia has been used in dental drilling procedures, such as those particularly in the Patent No. 3,085,465 to B. Brooks et al

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The United States was revealed by that an external, unidirectional magnetic field is produced over the affected area of the tooth. The drilling operation is then carried out so that the drill rotates in the field. This will put a in the drill Electricity is generated and this electricity acts directly on the nervous system of the affected tooth. E1ra better results are achieved by using a special drill embedded in an insulated coil of fine wire will. One coil line is connected to the drill bit and the other to the drill shaft. The one in the drilling} f ' Additional conductors embedded in the shank can generate higher voltages at lower strength fields in order to to achieve a better analgesic effect on the tooth nerves. However, certain adverse attendant circumstances do the known devices are impractical and reduce their effectiveness considerably. Such a disadvantage is the observed fluctuation in the voltage level of the desensitization current, depending on the arrangement of the drill in relation to the magnetic flux over the affected area of the patient. Reliable voltage levels are due to the distribution of the natural field of the magnetic flux density is difficult to maintain.

Older devices were due to the size of the permanent magnet and the size of the one wound on the drill Coil found impractical. In addition, such devices had to be wound with a suitable wire provided special drills can be used. This made it necessary to replace the whole set of simple drills or double it. Furthermore, there was due to a lack of concentricity of the drill and embedded The bobbin has a tendency to rotate unevenly. 'This irregularity is relatively high

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Turbine rotation speed particularly noticeable and had inadequate vibration and others Operational difficulties result, which significantly shortened the life of these known devices Special precautions were also necessary to eliminate side effects of the strong magnetic field, for example, glasses with metal frames and wristwatches had to be removed from the patients. Occasionally it was also noted a serious psychological aversion to the device placed around the patient's head.

Another disadvantage of the known dental drilling device is that after turning off the drive means, usually a high-speed turbine, the drill continues to rotate due to its torque ". It is therefore necessary to be extremely careful when removing the rotating bit from the tooth Take care to avoid accidental contact with otherwise healthy areas of the patient's tooth or mouth * u avoid.

The maintenance of the known drilling devices is expensive and time consuming. Sending the defective Apparatus to the manufacturer for repair is often required and has a significant loss of manpower and other expenses.

The aim of the present invention is to create a device which does not have these disadvantages.

According to the invention this is achieved in that a self-supporting and compact unit is provided which, in contrast to the known devices, no requires complicated preparation and maintenance. the

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The invention advantageously discloses at least one coil mounted in a handpiece, with a lead with the handpiece housing, and the other line with one Pain-producing tool, e.g. a dental drill, is electrically connected. However, see that other conductor shapes, such as a flat conductor or the like can be used in place of the coil at will without exceeding the scope of the invention will. A magnet, preferably a permanent magnet, is also in the vicinity of the coil in the handpiece appropriate. The usual turbine bearing unit can be provided to the magnet preferably with respect to the To rotate the bobbin, although the bobbin can be rotated without going beyond the scope of the invention. the Rotation of the permanent magnet causes its magnetic flux lines to move across the coil and thereby a Induce predetermined electrical voltage in the tool. After contact between the tool and produced in the patient's body, current flows through the patient to earth and thereby desensitizes the touched area.

In other words, the device is characterized in that the following parts are provided: a housing, a pain-causing medical tool connected to the housing and made of electrically conductive Material, a first point of an electrical circuit in the housing, a second point of one electrical circuit in the housing, mounted in the housing, electrically connecting the points of the circuit Means for conducting electricity to the area on the patient with one point of the circuit connecting means, a means connecting the tool to the other point of the circuit, in the housing *

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attached and one of the conductive means overlapping magnetic flux generating means and a with the housing associated means which move the one conducting means and the flow generating means with respect to one another and generated in the conductive means a predetermined voltage, whereby generating after contact between the work and the area current passes through the area and desensitizes it.

According to the invention, a large number of assembled units or components are provided for dental drilling work, which can easily be removed from the device for replacement or other maintenance. One of these units contains the electrical system, the preferably permanently attached conductor, or e.g. connects the coil with the rotary drill. In another unit, the turbine bearings, the clamping sleeve and the magnet should be included. Disused bearings or electrical contacts can therefore be easily serviced on the spot by simply replacing the faulty unit with a new one.

Another advantage of the present dental handpiece is that no special drills are used have to. Accordingly, there is no need for costly replacement or duplication of the whole Drill set, as was necessary in the known devices. The present device can be used in otherwise conventional dental systems can easily be incorporated.

In the invention braking means are also provided which act on the rotating drill, whereby after switching off the turbine drive, the speed of the drill is quickly returned to the idle state

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will. This arrangement serves to reduce the risk of accidental Injury to the patient when the drill is removed from the affected tooth down to a minimum to add.

Further details of the invention are to be explained and described in more detail using exemplary embodiments with reference to the attached drawings.

Fig. 1 is a partially cut-away side view an advantageous dental handpiece according to Principles of the invention,

Fig. 2 is an enlarged vertical partial section through the head of the handpiece shown in Fig. 1,

Fig. 3 is a section along line 3 - 3 in Fig. 2,

Fig. 4 is an enlarged partial vertical section through the head of another embodiment of the invention;

Fig. 5 is a section along line 5 - 5 in Fig. 4,

Fig. 6 is a partially sectioned side view of a key used to aid dental tools can be exchanged in the handpiece,

7 is a section along line 7-7 in FIGS. 6, and

FIG. 8 is a section along line 8-8 in FIG. 6.

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Subsequently, reference is made to the drawings. In Figs. 1 and 2, in particular, is an example
a dental handpiece, generally designated by the reference numeral Io, is shown with an elongated one
Handle 11 with flanged gripping areas 12 and one
Head 15. A pain producing tool 14 in which
present embodiment, a dental drill extends out of the head Ι} for machining a tooth l6. It should be noted, however, that the invention can be used with various types of pain producing medical tools and is not intended to be limited to dental drilling devices.

Fig. 1 shows, as an example, a schematic representation of the electrical circuit for production
electrical desensitization during a dental drilling process. As described below, current is generated within the head 13 during the drilling process. After the tooth 16 comes into contact with the drill 14, it flows
Electricity in the tooth, provided that the tooth is effective
is connected to a Hasse, which is advantageously the housing 17 of the handpiece Io. It has been observed that a current of approximately two microamps is sufficient to desensitize the nervous system of the tooth. The effect of this desensitization is limited to the affected tooth and only lasts as long as it is
Tooth is in contact with the drill Ik .

The handpiece Io can also use a conventional cooling system included, with a tube I5 through which a jet of water is straightened during the drilling process. A fiber optic system in the form of a light-conducting tube 2o for illuminating the bdr area can also be included in the handpiece.

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According to FIG. 2, the head Ij5 is preferably made of a A large number of contiguous housing parts assembled, all of which are made of corrosion-free steel or other Electrically conductive material can be made that is rigid enough to ensure a proper housing construction to build. A cap 19 closes the open end of the turbine housing 18 and can by means of a cooperating thread area

21 can be connected to the latter. The removable cap 19 provides easy access to the internal components of the device to facilitate assembly and repair.

The cap I9 is also with a central hole

22 provided, which has a reduced diameter range

23 and a larger diameter range 24 has. A Insert cover 26, preferably larger in the area 24 Diameter of the bore 22, can be provided to allow easy access to certain, Parts subject to friction erosion and easy replacement of the same as below described in more detail.

Since the head of a dental handpiece is intended for use in a patient's mouth, the area must the outer surface must be smooth and free of edges that could cause accidental injury. Accordingly, the insert 26 fits into the bore 22 such that its upper surface snugly into the outer edge the cap I9 passes. Under the circumstances it was considered suitable to provide the insert 26 with a pair of recesses 27 and 27a which are used for this purpose can be used to enter the required torque.

A turbine 28 is located in the turbine housing l8.

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arranges which on upper and lower bearings 29 and 29a is appropriate. A conventional supply pipe 3o leads the turbine from a remote source to the driving force Fluid, usually air or water. In operation, the fluid is directed onto the drive vanes 31, causing them to rotate will. An exit tube (not shown) or other exit means such as venting elements (not shown) can also be provided in the handpiece, around the fluid guided over the blades 31 remove the head. In the present embodiment, this residual fluid, in particular Air, proven to be a useful coolant for parts that have high frictional temperatures during work are exposed.

A preferably elongated rotor shaft or hub 32 is connected to the turbine blades 31 to to be driven by them and contains a central bore 33> which extends from its lower or outer end almost to the top of the shaft, so that the latter is in fact essentially tubular. The upper end of the bore is, as with reference number 4o specified, provided with a thread, so that a connection with a corresponding thread Clamping sleeve 34 can be produced. Rotor shaft 32 and Clamping sleeve 3 ^ each have outer extensions 35 and 36 with a preferably hexagonal outer surface. The rotor shaft and the clamping sleeve act as a clamping device together, as indicated by reference numeral 60, to hold the drill bit 14. Like in Pig. 2 specified, the drill can be inserted into the jig at any required depth.

The turbine unit 28 can be in a preferably 209843/0577 - Io -

hard rubber or neoprene chamber 37 is attached to to electrically isolate the unit from the housing 18 and also to mount the turbine firmly in the housing 18. the Hard rubber chamber is preferably provided with a longitudinal slot 38 for receiving a pair of guide pins 39 and 39a, which extend from the turbine housing 18 extend laterally inwards. These pins both serve to align the turbine 28 in the housing and to secure the hard rubber chamber so as to prevent the sleeve from moving during the drilling operation rotates with the turbine blades and the rotor shaft.

An electrical conductor means having a predetermined number of turns, preferably one Coil 4l (Fig. 3) can be mounted in the housing. This coil can be mounted on an armature or a coil former 42 to be appropriate. The number of windings can be different. But if, for example, a wire with a diameter of 0.127 is now is used, it has been noted that twenty-one turns is adequate when these requirements are also used can be modified depending on whether more or less tension is desired.

It is important to note that neither the shape nor the number of 13 effective conductive elements is to be limited. Instead of a coil, there are conductor shapes, such as flat conductors here or similar arrangements are also suitable. In the advantageous embodiment, however, there is a coil has been found suitable, albeit with other coils, e.g., two or more in series or in parallel, respectively can be used to increase the voltage or operational reliability as desired without doing so the scope of the invention would be exceeded. A leader

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43 of the coil is electrically connected to the housing l8, while the other conductor 44 is advantageously electrically connected to de.m drill 14 through the following contact means described in more detail.

One from a permanent magnet rotor 4-5 from preferably Sintered material existing magnet element can be at a short distance from the coil 4l, but from this by a Air gap 46 separate, mounted for rotation on the turbine rotor shaft 22. The rotor 45 is preferably ring-shaped, with permanently magnetized areas changing polarity at intervals around its circumference. The rotation occurs during the operation of the dental turbine of rotor shaft 32 and rotor 45 that all magnetic Areas of the rotor are moved past the coil windings 4l one after the other. According to the known principles an electrical voltage is induced in the coil when the magnetic flux lines pass the windings cross. For example, suitable analgesic results are obtained when this induced voltage is approximately 0.06 V, which gives an alternating current of essentially two microamps. The air gap 46 can adjusted to help determine suitable stress levels as desired.

It will be understood that numerous changes in terms of details of construction, combination and arrangement of the generator parts can be made without exceeding the scope of the invention. E.g. The particular arrangement of magnet and coil windings need not be that described above. It Adequate voltages were created when the windings were mounted for rotation on the turbine drive shaft and were surrounded or partially surrounded by a fixed permanent magnet. Other conductor elements can also be used

209843 / QS77 - 12 -

ments can be used instead of the coil 41 to the Cutting lines of magnetic flux. The present embodiment is advantageous in that it mechanically more efficient, a body of uniform density such as the permanent magnet rotor 45 at high Speed, and it has been found that voltages of greater reliability on this Manner and by using the coil 41 can be generated.

The rotor 45 is preferably coaxial with the shaft 52 attached so that its axis of rotation is substantially runs at right angles to the longitudinal axis of the coil. It is also advantageous that the bobbin 42 and the Rotor 45 are aligned substantially laterally to one another. Under such conditions are the coil windings 4l aligned in such a way that they intersect the highest density magnetic flux lines which originate from Rotor 45 go out.

An electrical contact between drill 14 and coil 4l can be established in various ways, e.g. by conventional brushes or by the bearing rings of the turbine unit. However, such an arrangement was made found to be a little underperforming. Furthermore, turbine drills can be rotated with about 500 or 400, ooo revolutions rotate per minute. It has been found that a suitable one for such high rotational speeds electrical connection made by permanent contact between a pair of adjacent contact buttons 47 and 48 will. The contact button 47 is advantageously made of hardened silicon carbide, but can also be made from other material such as corrosion-resistant steel and is connected to the inner end of the rotor shaft 52

209843/0577

blondes. The contact surface 49 of the button 47 is preferred just worked, however a substantially convex contact surface has also been found suitable.

The contact button 48 is connected to one side of a holding element or a disk 51, which in the Reduced diameter area 2J of bore 22 in the cap 19 is slidably disposed. The button 48 is also electrically conductive and is preferably made of a material such as silver graphite. The contact surface 49 of the button 47 abuts when the handpiece is actuated button 48. It should be noted that a sliding contact (not shown) also makes an effective connection able to produce and if necessary used instead of one or the other contact button 47 and * 48 can be.

The extremely high rotational speeds generated by the turbine cause constant erosion of the silver graphite button 48. In order to ensure permanent contact between the buttons 47 and 48, a spring 52 is arranged on the other side of the disk 51, namely between disk 51 and insert 26 so that the former is permanently tensioned against button 47. The spring 52 is preferably a conical coil spring so that it is compressed to the size of one of its coils. When the contact button 48 is new, the spring 5 ² between disk 5I and insert 26 is compressed and thereby stores energy. When the knob 48 begins to erode due to the rotational friction, the spring 52 gradually releases its stored energy, whereby the disk 51 and the eroding contact 48 are pressed in the longitudinal direction of the bore 22. When the button 48 is completely worn, there is another movement

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the disc prevented by a stop 5o, which preferably protrudes laterally from the side walls of the bore 22. The insert 26 can then be removed from the cap 19 unscrewed and the disc 51 simply by a new disc with contact button must be replaced. Another possibility would be the coil 41 and the disc 51 carrying cap 19 can be easily exchanged as one component.

At least one contact shoe 5j5 can be attached to the inner side wall of the housing 18. A feed or a socket 5 ^ is provided to the shoe 53 against to isolate electrical contact with the housing. A resilient contact arm 56 is attached to the disc 5I and electrically connected to the contact button 48. The arm 56 is biased against the shoe 55 to complete the circuit between the coil windings 4l and the drill 14 as described below. When the disk 51 moves by means of the spring 52, the arm slides 56 on the contact surface of the shoe in order to maintain the electrical connection between coil 4l and button 48. This sliding contact between arm 56 and shoe 53 causes an automatic self-cleaning, eliminating the possibility of work disruption due to soiled and unsuitable electrical lines are reduced to a minimum. '

In the event that one is outside the handpiece A local source of electricity such as an AC power source (not shown) is essentially required consisting of the disk 5I and the contact button 48 Component can be used to connect the external source to the smear generating tool. Of the Conductor from the source can be connected to contact button 48 in any manner known to those skilled in the art.

209843/0577 " ¹⁵ ~

Current from "this source therefore flows into the Button 47 and from there through an insulated conductor the pain-producing tool. It should be noted that a DC power source such as a battery cell can also be used, either outside or inside the handpiece, as desired, to provide the desensitization current to apply to the tooth or other affected area.

Using a dental handpiece such as that indicated by the numeral Io, current can flow from button 47 into turbine rotor J2, collet Jk and drill bit 14. By providing suitable feedback from the patient to the external source to complete the circuit, the drill-patient contact allows the current to flow through the drill and through the affected tooth to desensitize the latter and return to the source. It should be noted that the conductor from the external source can also be connected to the contact shoe 53 in any suitable manner. In this case, the resilient contact arm 56, as described above, can be used.

When the preferred shape of the dental handpiece Io is operated, the desensitization current flows through the the following circuit: from coil 41 through conductor 44 to contact shoe 55, in contact arm 56, to button 47, to the rotor shaft J52 and from there into the drill 14. If the Tooth 16 is properly connected to ground 17, the current flows into the tooth upon contact with the drill and is desensitized thereby the tooth nerves.

The connection between tooth and earth to close the circuit can be established in various ways will. For example, a can move from the handpiece housing to the

209843/0577 - 16 -

Patient extending wire conductors may be provided. A metal bracket (not shown) can be used to connect the conductor to the patient's lip. If no wire conductor is available, the operator can or the dentist closes the circuit by touching the patient while he is holding the dental handpiece holds. The patient and the handpiece can also be connected to a ground in some other way. It should be noted It will be understood that other techniques known to those skilled in the art may also be used without departing from the scope of the invention is exceeded.

Since in the preferred embodiment the electrical connection between the coil 41 and the button 48 is easily interrupted by simply removing the washer 51 and its contact arm 56 and button 58 from the housing 18 is withdrawn, such a component can easily be replaced by the user of the tool, when button 48 has become disabled. Such an arrangement serves to reduce the time wasted and the usual reduce costs associated with the maintenance of dental facilities to a minimum.

The contact shoe 5J3 is preferably with a vertical guide slot 57 is provided, which the contact arm 56 detects. The slot 57 serves to prevent that the disk 51 begins to move by means of the pressure transmitted by the button 48 when the turbine is actuated Turning forces.

The stability can be increased in that a second contact shoe in the housing 18 with respect to the Shoe 55 is provided symmetrically arranged. A second resilient contact arm 59, similar to contact arm 56,

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can be provided on the disc 51 for contacting the shoe 58 be. Although a contact shoe and contact arm found suitable for the present purposes others can be used in the present device without affecting the scope of the Invention would be exceeded.

Due to the constant contact of buttons 47 and 48 Significant frictional forces arise during the operation of the turbine. The inhibiting effect of such friction on the rotational speed of the turbine rotor - 32 is relatively insignificant when the turbine is started However, when the turbine is switched off, these frictional forces act as a brake to the rotational speed of the rotor 32 to decrease rapidly until it stops closing turn. This arrangement serves to reduce the possibility of injury to the tooth or mouth to a minimum, when the handpiece is removed from the affected area.

Figures 4 and 5 illustrate an embodiment of the invention using various pain-causing medical tools, particularly dental tools, like needles, probes and excavators and other similar tools interchangeable in connection with the handpiece Ho can be used. The arrangement magnet-electric Parts is essentially the same as in Fig. 1 to 3. In this embodiment, the Turbine unit 128 only for rotating the permanent magnet rotor 145. Accordingly, the coil 14l through the housing II8 can be connected to a known type of non-rotating metal jig 160, which can accommodate a variety of different medical tools. A contact between the coil l4l and the

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Jig 16o can be manufactured in any known manner, but it has been found to be advantageous. been to connect a conductor 3.44 to the cap II9 ", which in this embodiment serves as a mass. A Conductor 143 can be soldered to a metal ring Ιβΐ, that of the cap II9 through a nylon or Teflon bushing. 161 is isolated.

With this arrangement, movement flows in the coil of the magnet rotor 145 generated current from the coil l4l through the conductor l4; 5 to the ring Ιοί. Any suitable electrical conduction between ring 161 and the patient, as described above, can be used to establish the circuit Find use. After contact between the tool and the patient, the circuit is closed and the current flows through the drill into the tooth and to the mass, thereby desensitizing the affected tooth nerve.

Also belongs to the scope of the invention that the same dental handpiece Io either with drills or with other pain producing dental and medical tools can be used. E.g. if coil 4l and Shoe 53 of the embodiment of FIG. 2 on cap 19 are attached, the handpiece of FIG. 4 can simply be converted to drilling by the fact that the turbine unit 128 is replaced by the unit 28 with rotatable chuck and the cap II9 by the cap 19. One such interchangeability can be carried out simply and cheaply according to the invention.

In the event that the pain-producing medical tool or drill is not made electrically conductive material is made, it belongs to the range of the invention, current from the coil 4l to the affected area of the patient through other electrical lines

209843/0577 - 19 -

than to direct the tool itself. Additional probes made of electrically conductive material can Use or other means such as electrically conductive brackets or clamps can be provided as desired be to touch the affected area.

In FIGS. 6, 7 and 8 there is shown a key, designated generally by the reference numeral 7o, which is intended in particular for handling the rotatable clamping device 6o in order to facilitate the exchange of dental or medical tools in the handpiece Io. The key 7o preferably consists of a shaft or handle area 71 * at one end of which a piston 72 is attached for longitudinal movement with respect to the handle. The plunger can be attached to the handle in any suitable manner, but it has been found convenient to retain the plunger in the bore of an enlarged hollow area 73 so that the plunger can slide freely back and forth as desired when the wrench tool is in use will. A helical spring Tk is used to push the piston outward into the position shown by dashed lines in FIG.

A pair of laterally extending links 76 and 77 can be attached to the other end of the shaft 71 to grip the Handpiece Io be provided. These members preferably consist of one-piece molded wall parts that are separated from one another by a fixed, predetermined distance which is substantially the length of the

It

Head 13 of the handpiece corresponds / should be noted, however that the invention is not supported by these wall members is limited, and that other types of gripping means can be provided without thereby affecting the area of the Invention is exceeded. The wall members 76 and 77 need not be immobile. It can also be

209843/0577

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adjustable members find use, which are capable of several different types and sizes of dental handpieces to grab.

A radial slot 78 can be provided in the wall member 77 (Fig. 7). The slot 78 fits tightly the hexagonal extension 35 of the rotor shaft 32, if the head of the handpiece Io between the gripping members 76 and 77 according to FIG. 6 is arranged. The purpose of the Slot 78 is to hold the rotor shaft against rotation during handling of the jig.

The inner end 79 of the piston 72 is with a central bore provided, which has a region 82 of reduced diameter and a recessed region 83 (Fig. 8) has a larger diameter. The shape of the recessed area 83 corresponds to the shape of the extension 36 of the clamping sleeve, so that this extension is detected for independent movement against the rotor shaft 32 can be.

In use, the piston 72 is turned inwardly the tension of the spring 74 is pressed until the received Area 83 detects the extension 36 of the clamping sleeve. Of the Drill 14 extends into the remaining hole 8l without being able to cause damage. The drill 14 is turned by turning of the piston 72 is released, whereby in turn the sleeve 34 is rotated. The latter moves axially with respect to the rotor shaft 32, due to the movement translating properties of the thread area 4o. if the sleeve moves axially outward, can according to known design principles for jigs Grip strength around the drill, which can then be removed and replaced. The new drill can be

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209843 / 0S77

clamping device can be attached simply by reversing the direction of rotation of the sleeve .. A flanged area 84 is provided on the piston to facilitate manual rotation of the piston and sleeve.

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Claims (16)

- 22 - ■ 215A650 patent claims 1.) Medical device for touching an area on the body of a patient, characterized in that the following parts are provided: a housing (18, 118), a pain-causing medical tool (14, 114) connected to the housing made of electrically conductive material, a first point (43, 144) of an electrical circuit in the housing, a second point (44, 143) of an electrical circuit in the housing, mounted in the housing, the points of the circuit electrically connecting means (41, 14l) for Conducting electricity, connecting the area (16) on the patient to one point (43, 144) of the circuit Means, the tool (14, 114) with the other point (44, 143) of the circuit connecting means, im Housing attached and a conductive means overlapping magnetic flux generating means (45, 145) and a with the housing connected means (28), which the one conductive means and the positive generating means (45 * 145) in relation to each other / moved and in the conducting means (4l, l4l) generates a predetermined voltage, whereby after contact between the tool (14, 114) and the area (16) Electricity passes through the area and desensitizes it. 2. Apparatus according to claim 1, characterized in that the first point (43 * 144) of the electrical Circuit includes the housing (18, 118) and that the tool (14, 114) is electrically connected to it. - 23 209843/0577 3. Apparatus according to claim 2, characterized in that the second point (44, 143) of the electrical circuit includes an electrically conductive element (53, l6l) which is connected to the housing and is electrically isolated from it. 4. Apparatus according to claim 3 * characterized in that the housing (118) in its outer surface has a recess which is lined with electrically insulating material (162), and that the electrical conductive element is a strip (loo, l6l) of conductive material fastened in the recess. 5. Device according to one of the preceding claims, characterized. That the the flux generating means (45, 145) are rotatably mounted with respect to the conductive means (41, 14l). 6. Device according to one of the preceding claims, characterized in that the declines the flux generating means from a rotor (45, 145) consist of magnetic material, around the circumference of which magnetic pole areas of alternating polarity are arranged are, and that the conductive means consists of at least one coil (4l, 14l) with a predetermined number of turns consists. f 7. Apparatus according to claim 6, characterized in that the moving means is a turbine (28, 128) which serves to turn the rotor (45, 145). 8. Apparatus according to claim 6 or 7 * characterized in that the one coil (4l, l4l) contains a core element (42) attached to the housing, which 209843/0577 - 24 - ches is aligned substantially laterally to the rotor (45, 145), and that the windings on the element are appropriate. 9. Apparatus according to claim 8, characterized in that the pain-producing medical Tool (14) is a dental drill and that the turbine (28) serves to rotate the drill. 10. The device according to claim 9, characterized in that that the rotor (45) is connected to the drill (14) and rotates with it. 11. The device according to claim lo, characterized in that that the rotor (45) is mounted coaxially with the drill (l4), and that the axis of rotation of The rotor and drill run essentially at right angles to the longitudinal axis of the coil (4l). 12. The device according to claim 11, characterized in that that to the electrically connecting means a first electrically connected to the drill (14) Contact element (47) and a second contact element (48) belongs, which is electrically connected to the windings (4l) and is biased against the first contact element to establish an electrical connection therebetween, whereby an electrical voltage induced in the windings by the movement of the rotor (45) with the drill (l4) can be connected. 13. The apparatus according to claim 12, characterized in that the first and the second Contact element are two juxtaposed contact buttons (47, 48), each of which has a contact surface. - 25 - 209843/0577 25 - 215A650 14. The device according to claim 13 *, characterized in that the second contact element (48) includes a holding element (51) which extends in the longitudinal direction with respect to the first contact button (47) move / that the second contact button (48) is attached to one side of the holding element (51) and that a clamping element (52) touches the other side of the retaining element, in order to continuously compress the contact surfaces while the drill (14) is rotating. 15. Turbine unit for use in the medical device according to one of claims 1 to 14, characterized characterized in that it has an elongated, substantially tubular hub element (33) an inner and opposite outer end connected to the unit for being rotated therefrom to become that at least the outer end (35) substantially axially protrudes beyond the unit that an elongated, substantially tubular clamping sleeve element (34) is provided with an inner and an opposite outer end and fits concentrically into the hub, that the outer end (36) of the clamping sleeve protrudes substantially axially from the outer end (35) of the hub and that a movement-transmitting element (4o) is provided which connects the hub and the clamping sleeve, whereby locking the collet (34) against accidental axial movement with respect to the hub (32) able. 16. Device in particular for handling the unit according to claim 15, characterized in that that a shaft region (71) is provided, furthermore first member (76, 77) connected to the shaft and having a means (78) for securing the clamping sleeve (34) against rotation, - 26 -209843 ^ 0577 a second element (72) movably connected to the shaft (17o) and having means (8j5) for gripping the hub> whereby the clamping sleeve (3 ² O can be moved axially with respect to the hub (32)). 209843/0577 Blank page