WO2013029582A1

WO2013029582A1 - Drilling machine, in particular medical drilling machine, and drilling method

Info

Publication number: WO2013029582A1
Application number: PCT/DE2012/000787
Authority: WO
Inventors: Axel von FREYBERG; Dirk STÖBENER; Gert Goch; Michael Sorg; Rüdiger SPICHER
Original assignee: Universität Bremen; Roland-Klinik gGmbH
Priority date: 2011-08-26
Filing date: 2012-08-01
Publication date: 2013-03-07
Also published as: DE102011111671B4; DE102011111671A1

Abstract

A drilling machine (10), in particular a medical drilling machine, with a housing (12) which accommodates an electric motor (56) and a drill mechanism driven by the latter and having a drill (14), characterized in that it also has a device for measuring the depth of penetration of the drill, a device for measuring axial force, a device for measuring solid-borne noise, and a signal-evaluating device (62) for determining the length of the drilled channel (21) through the whole of the body (22) that is to be drilled, or as far as a material transition, in particular an abrupt material transition, in the body that is to be drilled, and a drilling method, in particular a medical drilling method, characterized in that, during the drilling of a drilled channel (21) in a body (22) that is to be drilled, the depth of penetration of a drill (14), the axial force with which the drill is pressed onto the body that is to be drilled, and the solid-borne noise in the body that is to be drilled are measured simultaneously, and the measured values are evaluated in order to determine the length of the drilled channel through the whole of the body that is to be drilled, or as far as a material transition, in particular an abrupt material transition, in the body that is to be drilled, and the length is output, in particular displayed.

Description

DRILL, ESPECIALLY MEDICAL DRILL, AND DRILLING

The present invention relates to a drilling machine, in particular a medical drill, and a drilling method, in particular a medical drilling method.

In surgery and orthopedics, metal implants are used for the stabilization of or in the bones (so-called osteosynthesis) as part of the treatment of fractures, but also in the correction of congenital or acquired malpositions of the skeletal system. These surgical techniques of bone stabilization are used hundreds of thousands of times a year in Germany alone, but millions of them are used worldwide.

As osteosynthesis materials mostly screws or combinations of metal plates and screws have been used for decades. These implants are usually made of stainless steel, increasingly more of a titanium alloy.

For stable anchoring of the screws, it is necessary to create targeted drilling channels in the bone. In this case, the implanted screw with the posterior bone wall close exactly, as a screw projection leads to chronic irritation and damage to the surrounding soft tissues. A too short selected screw can in turn lead by loosening into an implant failure with the result of bony instability. The determination of the correct screw length is routinely routinely done in the art by measuring the depth or length of the applied drilling channel. The measuring instrument is a mechanical measuring gauge. However, the measurement process proves to be problematic again and again in everyday life, since metrologically caused erroneous and sometimes non-reproducible length determinations of the drilling channels. The error-prone measurement then inevitably leads to the risk of implanting a wrong screw length with the above-mentioned adverse consequences. A control of the screw length is usually only possible by intraoperative X-ray examination, since the opposite end of the screw from the surgical incision (access) is not visible and is covered by the opposite bone wall. During a running operation, only a part of the faulty determinations is usually recognized, so that a correction is still possible here. However, another portion of the incorrectly determined screw lengths remains undetected and therefore uncorrected. These measurement errors have adverse consequences especially for the patient, but also for the involved surgical and anesthesia team. In addition to the health disadvantages for the patient and the economic consequences of the necessary follow-up interventions, possible demands for recourse to the hospital operator or the operating surgeon can be expected.

The problem described above by way of example for the medical field is quite generally in cases when one can not look into the body to be drilled and or when the side of the body to be drilled away from the entry point of the drilling channel is not optically accessible. In addition, the body to be drilled can not only consist of a uniform material but, for example, of several material layers or be a hollow body. The drilling channel does not always have to extend through the entire body, but could, for example, only be necessary through one or more layers of material.

The invention is therefore based on the object, an accurate measurement of lengths of drilling channels, especially if you can not look into the body to be drilled and / or the side of the drill body facing away from the entry point of the drilling channel is not optically accessible.

According to the invention, this object is achieved by a drill, in particular a medical drill, with a housing in which a motor, preferably an electric motor, and a drilling mechanism driven by it are arranged with a drill, characterized in that it further comprises a drill penetration depth measuring device for measuring the penetration depth during drilling of a drilling channel into a body to be drilled, an axial force measuring device for measuring the axial force with which the drill is pressed onto the body to be drilled, during drilling, a structure-borne sound measuring device for measuring the sound in the body to be drilled during drilling and a signal evaluation device for evaluating the measured values supplied by the drill penetration depth, the axial force measuring device and the structure-borne sound measuring device for determining the length of the drilling channel through the entire body to be drilled or up to one, in particular jump ften, has material transition in the body to be drilled. The body to be drilled may be, for example, a human or animal bone.

According to a second aspect, this object is achieved by a drilling machine, in particular a medical drill, with a housing in which a motor, preferably an electric motor, and a drilling mechanism driven by the latter are arranged with a drill, characterized in that it further comprises a drill penetration depth measuring device Measurement of the penetration depth of the drill while drilling a Bohrkanals in a body to be drilled, an axial force measuring device for measuring the axial force with which the drill is pressed onto the body to be drilled, while drilling, a reflection measuring device for measuring the reflection of light to the Drilling body in front of the drill bit during drilling and a signal evaluation device for evaluating the delivered by the Bohringeindringtiefen-, the Axialkraftmess- and the reflectance measurement values for determination the length of the Bohrkanals. Through the entire body to be drilled through or up to a, in particular abrupt, material transition in the body to be drilled.

Furthermore, this object is achieved by a drilling method, in particular medical drilling method, characterized in that during the drilling of a Bohrkanals in a body to be drilled, the penetration depth of a drill, the axial force with which the drill is pressed onto the body to be drilled, and the structure-borne sound measured simultaneously in the body to be drilled and the measured values for determining the length of the drilling channel through the entire body to be drilled through or to a, in particular jump, material transition in the body to be drilled are evaluated and output the length, in particular is displayed. As a motor, for example, a compressed air or hydraulic motor can be used.

Furthermore, according to a second aspect, this object is achieved by a drilling method, in particular a medical drilling method, characterized in that, during the drilling of a drilling channel into a body to be drilled, the penetration depth of a drill, the axial force, with the drill is pressed onto the body to be drilled, and simultaneously measuring the reflection of light on the body to be drilled in front of the drill bit and evaluating the measured values for determining the length of the drill channel through the entire body to be drilled or until a, in particular erratic, material transition in the body to be drilled and the length is output, in particular is displayed.

In the drilling machine according to the second aspect, it can be provided that it has a Kösmerschallmessinrichtung for measuring the sound in the body to be drilled during drilling.

According to a particular embodiment of the invention, the drill is a hand drill (also called hand-operated drill). According to a further particular embodiment of the invention, the drill penetration depth measuring device comprises a sleeve concentrically surrounding the drill, which is elastically biased over a displacement region in the longitudinal direction of the drill and in a forwardmost to the tip of the drill position of the displacement region, and a displacement sensor for detecting during the drilling of the sleeve from putting on the body to be drilled from the sleeve to the rear traveled displacement distance. The sleeve may also be used as a drill sleeve for soft tissue protection during a drilling operation.

Alternatively, the drill penetration depth gauge includes a rod extending parallel to the drill and slidably biased across a translation region in its longitudinal direction and resiliently biased in a forward most forward position of the displacement region, and a displacement sensor for sensing during drilling of the rod Placing on the body to be drilled from the rod to the rear traveled displacement distance.

Again alternatively, the drill penetration depth measuring device comprises an optical distance meter, in particular a laser distance meter, for determining the distance of the drilling machine to a body to be drilled during the drilling of a drilling channel in the same.

On the other hand, it is also conceivable that the drill penetration depth measuring device has an acoustic distance meter, in particular ultrasonic distance meter, for determining the distance of the drill to a body to be drilled during the drilling of a drilling channel in the same.

Expediently, the axial force measuring device has a pressure sensor, in particular a load cell. Advantageously, the pressure sensor is arranged between the rear end of the drill and a tool shaft associated with the drilling mechanism or on or in the tool shaft.

Also advantageously, the structure-borne sound measuring device has a vibration sensor between the rear end of the drill and the tool shaft or on or in the tool shaft.

According to a further particularly preferred embodiment, a vibration exciter for the active excitation of mechanical vibrations in the drill is provided. In particular, a preferably mechanical coupling can be provided, which is designed such that it couples oscillations generated by the vibration exciter only when the drill experiences a counterpressure after being placed on a body to be drilled. This variant with active vibration excitation instead of a passive method, preferably in the kHz range, has the advantage that the frequency of the introduced oscillation is known and thus the signal evaluation is simplified. As an alternative to the mechanical coupling, it is also possible, for example, to use an axial force sensor or pressure sensor for switching the active oscillation excitation on and off as a function of force or pressure.

Conveniently, a rotation angle sensor for detecting the rotational speed and / or the rotational angle of the drill during drilling is provided.

Advantageously, the detected rotational speed and / or the detected rotational angle is / are also fed to the signal evaluation device for evaluation and for determining the length of the drilling channel. Alternatively or additionally, a torque sensor for detecting the torque of the drill during drilling may be provided. In particular, it may be provided that the detected torque is also supplied to the signal evaluation device for evaluation and for determining the length of the drilling channel.

Conveniently, an automatic shutdown device for automatic shutdown is provided after detecting a complete piercing.

In the drilling method according to the second aspect, it can be provided that, while drilling a drilling channel into a body to be drilled, the penetration depth of a drill, the axial force with which the drill is pressed onto the body to be drilled, and the reflection of light on the body drilling body before the drill tip measured simultaneously and the measured values for determining the length of the drilling channel through the entire body to be drilled through or to a, in particular erratic, material transition in the body to be drilled are evaluated and the length spent, in particular is displayed.

Finally, the dependent claims 21 to 26 relate to advantageous developments of the drilling process.

The invention is based on the surprising finding that the simultaneous measurement of the penetration depth of the drill, the axial force and the structure-borne noise and / or the reflection of light in a simple and fast way, the complete penetration of a body or the penetration of one or more material layer (s ) of a body and thereby determines the length of a Bohrkanals through the entire body or by one or more material layer (s) and / or material transitions and / or material thicknesses can be determined. With regard to the input in connection with the drilling of bone described problem, the present invention provides a work easier, namely, instead of the previously required three steps to Insertion of screws (drilling, measuring the length of a Bohrkänals and insertion of the screw) only two steps (drilling and simultaneous measurement of the length of a drilling channel and insertion of the screw) are required. In addition, the length of the ^'drill channel can measure more accurately than before. This is due to the additional measurement of structure-borne noise that occurs when drilling a bone. Since bones are made up of different layers, drilling produces different vibrations in frequency spectrum and amplitude. When the drill is placed on the outer layer of bone (cortical bone), the vibrations change compared to drilling in the trabeculae or in the bone marrow cavity. When the drill emerges from the bone, in turn, the vibrations caused by the drilling process decrease sharply. The vibrations recorded by a structure-borne sound measuring device can be analyzed by a signal evaluation device. The vibration profile can be used to identify the time of entry and exit of the drill into and out of the bone.

In a particular embodiment, the measurement of structure-borne noise is used to determine the time of the entry of the drill into a bone and the time of its exit from the bone and the length of the drill channel on the basis of the drill penetration depths measured at the respective times and the formation of the path difference determine. The Axialkxaftmessung may - especially in this context - have the task of avoiding misdetection of the exit of a drill from a bone, for example, when interrupting the drilling process by a surgeon.

Further features and advantages of the invention will become apparent from the appended claims and the following description in which several embodiments are explained in detail with reference to the schematic drawings. Showing:

Figure 1 is a side view partly in section of a drill according to a particular embodiment of the invention in use; a side view partially in section of a drill according to another particular embodiment of the invention in use;

a side view partially in section of a drill according to another particular embodiment of the invention in use;

a side view partially in section of a drill according to a particular embodiment of the invention in use;

Figure 5 is a side view, partly in section, of a drilling machine according to another particular embodiment of the invention;

Figure 6 is a side view of a drilling machine according to another particular

Embodiment of the invention in use;

Figure 7 is a side elevational view partly in section of a drilling machine according to another particular embodiment of the invention;

two graphs, the upper of which shows the temporally resolved amplitude values in arbitrary units for different frequency components of the structure-borne sound signal as a function of time and the lower one the measured amplitude of structure-borne noise in arbitrary units as a function of time; and

Figure 9 is a side view partly in section of a drill according to another particular embodiment of the invention. FIG. 1 shows the front part of a drilling machine 10 with a housing 12 in which an electric motor (not shown) and a drilling mechanism driven by it are arranged with a drill 14. The drilling machine 10 has a drill penetration depth measuring device. This comprises a sleeve 16 concentrically surrounding the drill sleeve 16, which is resiliently biased over a displacement region in the longitudinal direction of the drill 14 and in a frontmost to the tip 18 of the drill 14 position of the displacement region, and a displacement sensor 20 for detecting during drilling a drilling channel 21 from the sleeve 16 from placing on a body to be drilled 22 of the sleeve 16 to the rear traveled displacement distance. In the present example, the body 22 is a cylindrical hollow body.

The embodiment shown in Figure 2 differs from that of Figure 1 in that instead of the sleeve. 16 a parallel to the drill 14 extending rod 24 is provided which is resiliently biased over a displacement region in its longitudinal direction and in a forwardmost to the tip 18 of the drill 14 towards the position of the displacement region. The body 22 to be drilled is exactly as in FIG. 1 a cylindrical hollow body.

The embodiment shown in FIG. 3 differs from the embodiment shown in FIG. 1 in that, instead of the sleeve 16 and the displacement sensor 20, an optical distance meter 26 is provided for determining the distance of the drilling machine 10 to a body 22 to be drilled during the drilling of a drilling channel 21 is provided. The optical distance meter includes a laser as a transmitter of light and a receiver of light reflected on the surface of the body 22.

In the embodiment shown in FIG. 3, the body 22 is a workpiece consisting of several different material layers 28, 30, 32, and 34. The embodiment illustrated in FIG. 4 differs from the exemplary embodiment shown in FIG. 3 in that instead of an optical distance meter 26, an acoustic distance meter 36 is provided. This has an ultrasonic transmitter and an ultrasonic receiver.

Although not shown in FIGS. 1 to 4, the drilling machines 10 shown therein additionally have an axial force measuring device for measuring the axial force with which the drill 14 is pressed onto the body 22 to be drilled, during drilling, and a

for measuring the sound in the body to be drilled 22 during drilling and a signal evaluation device for the evaluation of the Bohrereindringtiefen-, the Axialkraftmess- and the

g8li8fisrt8n measured values for determining the length of the drilling channel 21 through the entire body to be drilled 22 through or until a, in particular abrupt, material transition in the zuφεΓ to be drilled, for example, when passing from the wall of Ηο1ι ^ 0 εΓ5 in the cavity or at the transition from one layer of material to another.

FIG. 5 likewise shows a part of a drilling machine 10 according to a particular embodiment of the invention. This can be used as a hand drill just like the drills shown and described above. In addition, it can also be used in particular for drilling human or animal bones. It has a housing 12 in which an electric motor (not shown) and a drill mechanism driven by it are arranged with a drill 14. The drilling mechanism includes a tool shaft 38 (drill pipe). Along the tool shaft 38 are starting from the drill shank 40 to the rear, a pressure sensor 42 for measuring the axial force with which the drill is pressed on the zuφεΓ to be drilled while drilling, a rotation angle sensor 44 for detecting the speed and / or the rotation angle of Drill 14 during drilling, a, preferably inductively executed, vibration sensor 46 for measuring the sound in the to be drilled ΚοφεΓ 22 (Κ0φεΓ5ϋ1 11) during drilling, είη 8kktromagn8tisch8r vibration exciter 48 for the active excitation of mechanical vibrations in the drill 14 and a Torque sensor 50 for detecting the torque of the drill 14 during drilling provided. The tool shaft 38 is supported so that the drill 14 can make small axial movements to enable the active vibration excitation by means of the electromagnetic vibration exciter 48. A signal evaluation device (not shown) in the drilling machine 10 evaluates the depth of penetration of the drill 14 during drilling of a drilling channel into the body as measured by a drill penetration depth gauge (not shown) of the drilling machine 10 and that of the pressure sensor 42, the rotation angle sensor 44, the drill Vibration sensor 46 and the torque sensor 50 provided measurements for determining the length of the drilling channel 21 from.

In the example shown in FIG. 5, an active excitation of mechanical oscillations takes place by means of an inductive system with an electromagnetic excitation system (electromagnetic vibration exciter 48). The electromagnetic vibration exciter 48 has for this purpose a coil or comprises these.

The spool shown at 48 in Figure 5 can also be used to measure the axial movement of the tool shaft 38 and thus also the drill 14 by causing the axially moving tool shaft 38 in the spool to change magnetic field inducing a voltage. The magnitude of the induced voltage depends on the amplitude and the acceleration of the axial movement. Thus, the electromagnetic vibrational excitation system could be used as a sensor for the axial movement of the drill 14 and thus for a material transition. For inductive measurement of the axial movement, however, it could be practicable in certain cases to provide a further coil along the tool shaft 38.

Instead of the determination of the axial movement and thus the determination of a material transition by vibration excitation with constant energy, which can also be called soft vibration excitation, could also be a "hard" Vibrational excitation occur, namely with constant frequency and amplitude, for example by means of a piezo actuator. It is important to note that the above-described aspect of the measurement of the axial movement and the determination of a material transition can be additionally, but also alternatively designed to the embodiments described above.

6 shows an embodiment of a drill 10 in use when drilling a femur (femur) 52. Said drill has a housing 12, whose rear end is angled and forms a handle 54. In the housing, inter alia, an electric motor 56 and driven by this drilling mechanism with a gear 58, a tool shaft 38 and a drill 14 are arranged. As with the drilling machine shown in FIG. 1, a sleeve 16 and a displacement sensor 20 are provided for measuring the depth of penetration of the drill while drilling a bore into the femur 52. Furthermore, the drill along the tool shaft 38, starting from the drill shank 40 to the rear to a vibration sensor 46 and a pressure sensor 42. A piezo vibration exciter 60 (piezo shaker) is arranged next to the tool shaft 38 and thus coupled to the coupling of actively generated mechanical vibrations. In addition, the drilling machine 10 also contains a signal evaluation device 62 together with a display device for evaluating and displaying the measured values supplied by the displacement sensor 20, the vibration sensor 46 and the pressure sensor 42 for determining the length of the drilling channel through the entire body 22 to be drilled or up to one, in particular erratic, material transition in the body to be drilled 22nd

The penetration depth of the drill 14 is measured by means of the displaceable sleeve 16, which is coupled to the displacement sensor 20 in the drilling machine. For this purpose, the sleeve 16 is placed on the femur 52 and the rotating drill 14 is pressed against the femur 52. Once a contact is made, the axial force can be measured via the pressure sensor 42. From this point, the displacement of the sleeve 16 by means of the displacement sensor 20 is measured until the axial force at the exit of the Drill 14 from the femur 52 abruptly decreases. Bones usually consist of different layers. The bone wall (cortical bone) is usually harder than the inside of a bone (cancellous bone). This has the consequence that the axial force varies during the drilling process.

The path difference between the placement of the drill 14 and the detected exit of the drill 14 on the opposite side of the femur 52 corresponds to the length of the drilling channel. With the aid of the signal evaluation device 62, the measured values of the displacement sensor 20 and of the pressure sensor 42 are combined with one another and evaluated for the determination of the length of the drilling channel. For this, the signal evaluation should be designed so that it provides reliable measured values for different bone types and drilling scenarios. In addition, the measured values of the vibration sensor 46, which detects the vibrations that occur when drilling the bone, are used. Based on the thus determined length of the drilling channel screws can then be selected in the appropriate length.

The drilling machine 10 shown in FIG. 7, in which the drill penetration depth measuring device is not shown for the sake of clarity, differs, inter alia, from the drilling machine shown in FIG. 5 in that the vibration exciter is a piezo vibration exciter 60. In addition, it differs from the embodiment shown in Figure 6 in that it is a coupling 64 for mechanically coupling the vibrations of the piezoelectric vibrator 60 as soon as an axial force acting on the drill 14, is provided.

FIG. 8 shows exemplary results of structure-borne sound measurements during drilling in a bone (bovine upper leg, hind leg). The structure-borne noise was measured by means of a piezo-vibration sensor, which was located on an aluminum rod, which was mechanically coupled to the bone surface.

In the figure 8 a distinction is made between the time periods 1, 2, 3 and 4. Pierce the first bone cortex

Here is the occurrence of the drill and the decrease of bone material to recognize (rising edge). The rapid drop of the curve at point b marks the time at which the two preceding cutting edges of the drill can no longer detect any material, i. H. At time b, the drill has already broken through the first bone cortex.

Bore in the bone marrow

Here the bone marrow is drilled. The end of this time range is the peak at the end of the interval, which is due to the impact of the drill bit on the inner wall of the bony cortex.

Piercing the second bone cortex

In area 3, the hooking of the main cutting edge of the drill with the hard bone cortical material can be seen. The second peak in area 3 marks the end of the drilling process - breaking the drill through the second bone wall.

Drilling at idle and stopping the rotation

At the beginning of area 4, the falling rotational speed of the drill can be seen until the drill spindle is completely stopped. Signals in the range 4 clearly differ from the previous drilling process and can therefore be well analytically differentiated from the drilling process.

Figure 9 shows the front part of a drill 10 according to another particular embodiment of the invention with a housing 12 in which an electric motor (not shown) and a driven by this drilling mechanism with a drill 14 are arranged. The drill 10 has a drill penetration depth gauge, which is not shown for clarity. For example, it may be a drill penetration depth gauge shown in any of FIGS. 1-3. In addition or as an alternative to a structure-borne sound measuring device (not shown) for measuring the sound in a body to be drilled during drilling, it has a reflection measuring device 65 for measuring the reflection of light on the body to be drilled in front of the drill bit during drilling. For this purpose, the drill 14 has in the middle of its longitudinal extent a channel 66 (optical tunnel / optical measuring channel). The reflection measuring device 65 has a light source 68, a light coupling element 76 and a light guide 70 for coupling and directing light onto the body to be drilled in front of the drill bit. The coupled-in light is partially reflected back and fed via the light guide 70 and a light output element 74 to a light sensor 72. The light supplied to the light sensor 72 is evaluated. The evaluation is based on the assumption that the reflected light will be different due to the different optical properties of the different material layers 28, 30, 32 and 34. For example, the light intensity and with a color-sensitive light sensor can evaluate the spectral light distribution.

The embodiment shown in FIG. 9 additionally has an axial force measuring device (not shown) for measuring the axial force with which the drill 14 is pressed onto the body 22 to be drilled, during drilling, and a signal evaluation device for evaluating the depths of the drill penetration, the axial force. , the reflection and optionally also the structure-borne sound measuring device supplied measured values for determining the length of the drilling channel 21 through the entire body 22 to be drilled through or up to a, in particular abrupt, material transition in the body to be drilled, for example, in the transition from one material layer to another , If the reflection measuring device 65 in addition. is provided to the structure-borne sound measuring device, so the significance of the overall system should be increased and the overall system can be made more robust.

The features of the invention disclosed in the foregoing description, in the drawings and in the claims may be essential both individually and in any combination for the realization of the invention in its various embodiments.

Claims

claims

Drilling machine (10), in particular a medical drill, with a housing (12) in which a motor, preferably an electric motor (56), and a drilling mechanism driven by the latter are arranged with a drill (14), characterized in that

it further comprises a drill penetration depth measuring device for measuring the penetration depth of the drill while drilling a drilling channel (21) in a-to-be-drilled body (22),

Axialkraftmesseinrichtung for measuring the axial force with which the drill (14) is pressed onto the body to be drilled (22), while drilling,

a structure-borne sound measuring device for measuring the sound in the body to be drilled (22) during drilling and

a signal evaluation device (62) for evaluating the measured values supplied by the drill penetration depth, the axial force measuring device and the structure-borne sound measuring device for determining the length of the drilling channel (21) through the entire body (22) to be drilled or up to a, in particular erratic, material transition into having the body to be drilled (22).

2. Drilling machine (10), in particular medical drill, with a housing (12) in which a motor, preferably an electric motor (56), and driven by this drilling mechanism with a drill (14) are arranged, characterized in that it further comprises a drill penetration depth measuring device for measuring the penetration depth of the drill while drilling a drilling channel (21) in a body to be drilled (22),

Axialkraftmesseinrichtung for measuring the axial force with which the drill (14) is pressed onto the body to be drilled (22) ^" , while drilling,

a reflection measuring device (65) for measuring the reflection of light to the body to be drilled (22) in front of the drill bit during drilling and

a signal evaluation device (62) for evaluating the measured values supplied by the drill penetration depth, the axial force measuring and the reflection measuring device (65) for determining the length of the drilling channel (21) through the entire body (22) to be drilled or up to one, in particular abrupt , Material transition in the body to be drilled (22).

Drilling machine (10) according to claim 2, characterized in that it has a Kö sound-measuring device for measuring the sound in the body to be drilled (22) during drilling.

Drilling machine (10) according to one of the preceding claims, characterized in that it is a hand drill.

Drilling machine (10) according to one of the preceding claims, characterized in that the drill penetration depth measuring device a sleeve (16) surrounding the drill (14) concentrically over a displacement area in the longitudinal direction of the drill (14) and in a front to the top (18). the drill bit (14) position of the shift range is resiliently biased, and a displacement sensor (20) for Detecting the during drilling of the sleeve (16) from placing on the body to be drilled (22) of the sleeve (16) to the rear traveled displacement distance.

6. Drilling machine (10) according to one of claims 1 to 4, characterized in that the Bohrereindringtief enmesseinrichtung a parallel to the drill (14) extending rod (24) which is displaceable over a displacement region in its longitudinal direction and in a front to the top of A displacement sensor (20) for detecting the during drilling (14) of the rod (24) from placing on the body to be drilled (22) of the rod (24). Having moved backwards displacement distance.

7. Drilling machine (10) according to one of claims 1 to 4, characterized in that the Bohrereindringtiefenmesseinrichtung an optical distance meter (26), in particular laser distance meter, for determining the distance of the drill (10) to a body to be drilled (22) during drilling a Bohrkanals (21) in selbigen has.

8. Drilling machine (10) according to one of claims 1 to 4, characterized in that the Bohrereindringtief enmesseinrichtung an acoustic distance meter (36), in particular ultrasonic distance meter, for determining the distance of the drill (10) to a body to be drilled (22) during the Drilling a Bohrkanals (21) in selbigen.

9. Drilling machine (10) according to one of the preceding claims, characterized in that the axial force measuring device comprises a pressure sensor (42), in particular a load cell.

10. Drilling machine (10) according to claim 9, characterized in that the pressure sensor (42) between the rear end of the drill (14) and a drilling mechanism associated tool shaft (38) or on or in the tool shaft (38) is arranged.

1 having a drill (10) according to any one of the preceding claims, characterized in that the structure-borne sound measuring device comprises a vibration sensor (46) between the rear end of the drill (14) and the tool shaft (38) or on or in the tool shaft (38).

12. Drilling machine (10) according to one of the preceding claims, characterized in that a vibration exciter (48) for actively exciting mechanical vibrations in the drill (14) is provided.

13. A drill (10) according to claim 12, characterized in that a preferably mechanical coupling (64) is provided, which is designed so that it from the vibration exciter (48) generated vibrations only coupled when the drill (14) touchdown on a body to be drilled (22) experiences a back pressure.

14. Drilling machine (10) according to one of the preceding claims, characterized in that a rotation angle sensor (44) for detecting the rotational speed and / or the rotational angle of the drill (14) is provided during drilling.

15. A drilling machine (10) according to claim 14, characterized in that the detected rotational speed and / or the detected rotational angle is also the signal evaluation device (62) for evaluation and for determining the length of the drilling channel (21) is supplied / are.

16. A drilling machine (10) according to any one of the preceding claims, characterized in that a torque sensor (50) for detecting the torque of the drill (14) is provided during drilling.

17. Drilling machine (10) according to claim 16, characterized in that the detected torque is also the signal evaluation device (62) for evaluation and for determining the length of the drilling channel (21) is supplied.

18. Drilling machine (10) according to any one of the preceding claims, characterized in that an automatic shutdown device is provided for automatic shutdown after detecting a complete piercing.

19. Drilling method, in particular medical drilling method, characterized in that during the drilling of a Bohrkanals (21) in a body to be drilled (22) the penetration depth of a drill (14), the axial force with which the drill (14) to be drilled Body (22) is pressed, and the structure-borne noise in the body to be drilled (22) measured simultaneously and the measured values for determining the length of the Bohrkanals (21) through the entire body to be drilled through (22) or up to a, in particular erratic, Material transition in the body to be drilled (22) are evaluated and output the length, in particular is displayed.

20. Drilling method, in particular medical drilling method, characterized in that during the drilling of a Bohrkanals (21) in a body to be drilled (22), the penetration depth of a drill (14), the axial force with which the drill (14) to be drilled Body (22) is pressed, and simultaneously measured the reflection of light on the body to be drilled (22) before the drill bit and the measured values for determining the length of the Bohrkanals (21) through the entire body to be drilled (22) or up to a, in particular abrupt, material transition in the body to be drilled (22) are evaluated and the length spent, in particular is displayed.

21. Drilling method according to claim 20, characterized in that during drilling the structure-borne noise in the body to be drilled (22) is measured simultaneously and the measured values also for determining the length of the drilling channel (21) through the entire body to be drilled (22) or to a, in particular erratic, material transition in the body to be drilled (22) are evaluated.

22. Drilling method according to one of claims 19 to 21, characterized in that during the drilling mechanical vibrations actively generated and coupled into the drill (14).

23. A drilling method according to claim 22, characterized in that mechanical vibrations outside of the drill (14) actively generated and in the drill (14) are preferably coupled only when the drill (14) after placing on a body to be drilled (22 ) experiences a back pressure.

24. Drilling method according to one of claims 19 to 23, characterized in that the speed and / or the angle of rotation of the drill (14) detected during drilling and also for the evaluation for determining the length of the Bohrkanals (21) is / are used.

25. Drilling method according to one of claims 19 to 24, characterized in that the torque of the drill (14) detected during drilling and also for the evaluation for determining the length of the Bohrkanals (21) is used.

26. Drilling method according to one of claims 19 to 25, characterized in that the measured values are also used to determine material transitions and / or for determining material layer thicknesses.

Drilling machine

casing

drill

shell

top

displacement sensor

drill hole

body

Rod

optical distance meter

Layer the material

acoustic distance meter

tool shaft

drill shank

pressure sensor

Rotation angle sensor

vibration sensor

electromagnetic vibration exciter torque sensor Thighbone handle

electric motor

transmission

Piezo vibration exciter Signal evaluation device Coupling

Reflection measuring device channel

light source

optical fiber

light sensor

Lichtauskoppelelement Lichteinkoppelelement