2-in-1 operation medical motor handpiece and handheld instrument

Abstract

The present invention relates to a medical motor handpiece (2) for driving a distal end effector (8, 22). The motor handpiece (2) comprises a handle portion (4) and a preferably sleeve-shaped operating element (12). The operating element (12) is rotatably held at the distal end of the handle portion (4) about the handle longitudinal axis and is coupled to the end effector (8, 22) so as to convert rotational movement of the operating element (12) in a first rotational direction into movement of the end effector (8, 22) and to provide a function to the end effector (8, 22) when the operating element (12) is rotated in a second rotational direction opposite the first rotational direction. The present invention also relates to a medical handheld instrument (1) including the above-mentioned medical motor handpiece (2), and an end effector (8, 22) coupled to the motor handpiece (2) via a shaft (10, 20) for transmitting torque from the motor handpiece (2) to the end effector (8, 22).

Description

[Technical Field]

[0001] The present invention relates to a medical motor handpiece for driving a distal end effector (tool head), the motor handpiece having a handle portion. [Background technology]

[0002] [Background of the invention] Modern minimally invasive surgical procedures use such tools and associated handpieces and handheld instruments for, for example, the treatment of bone and cartilage in arthroscopic interventions, spinal surgery and similar orthopedic procedures, and the processing of organic materials in neurosurgery. These tools have a handpiece (handle) and, in some cases, an interchangeable effector (e.g., a milling cutter, rotary knife, grinding head, etc.). The effector is attached to the distal end of the tool shaft and can be driven to rotate. Depending on the intended application and tool speed, hydraulic, pneumatic, or electric motor drives are provided as tool drives. The tool drive is operatively connected to the tool and / or handheld instrument or to the tool head (effector) via a torque transmission cable in the handle. The tool drive may be integrated into the tool and / or handheld instrument or configured as an external drive unit coupled to the tool or handheld instrument via a power or torque transmission line.

[0003] To enable surgery in tight spaces, such as spinal surgery, it is advantageous to angle (tilt) the distal shaft portion of the shaft of a medical handheld instrument. In other words, the installation space and ease of management of the instruments used play an important role in surgical procedures, especially minimally invasive procedures. In particular, the instrument shaft in the region of the distal effector needs to be actively angled (intentionally via an actuation mechanism) in as small a space as possible.

[0004] Furthermore, the ability to quickly and easily change tools or effectors is advantageous in that it allows for rapid adaptation to changing operating conditions and / or working environments, minimizing strain on the patient.

[0005] [Latest technology] Angular shafts for medical handheld instruments are well known, and typically have a proximal shaft portion and an angular distal shaft portion. The distal and proximal shaft portions each have an oblique end (slanted end face) relative to their respective shaft axes. This means that one end (end face) of each of the distal and proximal shaft portions is not straight but is angled (angled). Each of the oblique end faces (slanted end faces) has substantially the same angle (operating angle). Thus, the oblique end faces (slanted end faces) fit together in such a way that the proximal and distal shaft portions form a straight shaft (tube) at a specific relative rotational position. When the distal shaft portion rotates around its longitudinal axis relative to the proximal shaft portion while the proximal shaft portion remains stationary, the distal shaft portion is necessarily angled due to the above-mentioned oblique end face.

[0006] Furthermore, Patent Document 1 (DE 102017010033 A1) also discloses a medical device comprising a guide unit having a guide tube with a longitudinal axis, a proximal first coupling part rigidly connected to the guide tube, and a cylindrical sleeve-shaped rotating head at the distal end. The medical device also comprises an actuation tube, which is axially movable within the guide tube and connected to the pivoting head, and which pivots the pivoting head via a proximal operating element. To more accurately align the distal guide element of a rotatable surgical tool and to angularly align the working head of such a tool, the operating element is rotatable about the longitudinal axis, whereby the pivoting head pivots in response to axial displacement of the actuation tube.

[0007] Furthermore, Patent Document 2 (U.S. Patent No. 7,585,300) and Patent Document 3 (U.S. Patent No. 10,070,872) disclose examples of surgical instruments that include a handpiece and a shaft housed within the handpiece, with a tool head pivotably connected to the distal end of the shaft. The tool head can be pivoted by a handwheel rotatably disposed on the handpiece. Similarly, Patent Document 4 (U.S. Patent No. 8,303,594) discloses a surgical handpiece in which the tool head is pivoted by a lever disposed on the handpiece.

[0008] Furthermore, Patent Document 5 (US Pat. No. 9,597,093) discloses a tool having a proximal end torqueably coupled to a drive unit and a distal end tool head, which can be pivoted relative to the tool shaft by rotating a sleeve located in the area of the tool head.

[0009] Other examples of handheld surgical instruments with a rotating tool that can be angled or pivoted relative to the handpiece are disclosed in, inter alia, U.S. Pat. No. 10,178,998, U.S. Pat. No. 10,307,180, or U.S. Pat. No. 10,524,820.

[0010] However, the state of the art always has the drawback that tools with angulation shafts require complex couplings, which do not easily allow for quick and easy decoupling. [Prior art documents] [Patent documents]

[0011] [Patent Document 1] German Patent Application Publication No. 102017010033 [Patent Document 2] U.S. Patent No. 7,585,300 [Patent Document 3] U.S. Patent No. 10,070,872 [Patent Document 4] U.S. Patent No. 8,303,594 [Patent Document 5] U.S. Patent No. 9,597,093 [Patent Document 6] U.S. Patent No. 10,178,998 [Patent Document 7] U.S. Patent No. 10,307,180 [Patent Document 8] U.S. Patent No. 10,524,820 Summary of the Invention

[0012] It is an object and goal of the present disclosure to eliminate or at least mitigate the drawbacks of the prior art, and in particular to provide an intuitive motor handpiece or handheld instrument that allows for easy and quick tool changes while simultaneously allowing for relative movement of the tools during operation.

[0013] The above-mentioned aims and objectives with regard to medical motor handpieces are solved by the invention as defined in claim 1. The invention is based on the realization of integrating two functions in one operating element (2-in-1 operation).

[0014] According to the invention, a medical motor handpiece is characterized by a preferably sleeve-shaped operating element, which is held at the distal end of the handle for rotation about the handle longitudinal axis and is connectable to an end effector such that rotational movement of the operating element in a first rotational direction is converted into movement of the end effector, and rotational movement of the operating element in a second rotational direction opposite the first rotational direction is converted into a different function of the end effector.

[0015] In other words, two different functions can be performed using one rotatable operating element, depending on the direction of rotation. This 2-in-1 operation of the motor handpiece eliminates the need for an additional operating element and allows for more intuitive operation.

[0016] Advantageous embodiments are set out in the dependent claims and are explained below.

[0017] In a preferred variation, the motor handpiece is connectable to the end effector via a shaft, and the operating element is capable of angling the end effector relative to the shaft during rotational movement of the operating element in a first rotational direction.

[0018] Furthermore, the end effector preferably includes a first coupling device and the shaft includes a second coupling device, the first and second coupling devices being operatively engaged with each other in the coupled state, and rotational movement of the operating element in the second rotational direction disengaging the first and second coupling devices.

[0019] In accordance with an advantageous embodiment of the present invention, the motor handpiece may be configured such that, in a plan view of the end effector, the first rotation direction is a clockwise rotation direction and the second rotation direction is a counterclockwise rotation direction.

[0020] Furthermore, it is advantageous if the handle portion and / or the operating element is provided with at least one indicator for indicating the movement and / or function of the end effector, preferably in the form of a numerical scale and / or pictogram.

[0021] According to a preferred further development, at least one latch and / or stop unit (locking device) may be provided (in particular in the form of a ball pressure element), which may be configured to limit the rotational movement of the operating element in the two end rotational positions and / or to increase the resistance to the rotational movement of the operating element in at least one intermediate rotational position.

[0022] An advantageous embodiment of the present invention may be characterized by a locking unit that, in the locked position, locks the rotational movement of the operating element in the first and second rotational directions and unlocks the rotational movement of the operating element in the released position. The locking unit may preferably be configured as a locking slide arranged on the operating element so that it can move axially between the locked and released positions. Furthermore, it is particularly advantageous if the locking slide has a spring element that presses the locking slide into the locked position.

[0023] Particularly preferably, the latch unit and / or the stop unit may be configured in the form of at least one ball pressure element and may have a spring load setting element (spring load adjusting element) (preferably in the form of a set screw) for steplessly variable adjustment of the spring load (elastic force) of the ball pressure element.

[0024] In an advantageous embodiment, the motor handpiece is connectable to the end effector via a shaft, which is connectable in a rotationally fixed manner to a rotation transmission sleeve of the motor handpiece, and the operating element preferably transmits its rotational movement to the rotation transmission sleeve via a radial adjustment pin.

[0025] According to an advantageous further development, the motor handpiece may have a connection at its proximal end for connecting the motor handpiece to the drive unit and the locking unit, the connection being connected to the operating element such that rotation of the operating element in the second rotation direction is locked when the motor handpiece is connected to the drive unit. Preferably, the locking unit may have a locking bolt connected to the operating element, which moves proximally when the operating element is rotated in the second rotation direction. For this purpose, the drive unit may also form a stop, whereby movement of the locking bolt can be prevented (locked) by the drive unit when the motor handpiece and the drive unit are coupled together.

[0026] The present invention further relates to a medical handheld instrument comprising the medical motor handpiece according to the present invention and an end effector coupled to the motor handpiece via a shaft, and transmitting torque from the motor handpiece to the end effector.

[0027] In other words, the invention relates to a (motor) handpiece with a rotary operating unit by means of which the removal of the tool can be initiated and the angulation of the distal tip can be adjusted in several stages. A safety function (on / off) ensures that the tool cannot be accidentally removed in the on state, as in known handpieces. [Brief explanation of the drawings]

[0028] The invention will now be described in more detail with reference to preferred construction examples and with reference to the following drawings:

[0029] [Figure 1] 1 shows a perspective view of a medical handheld instrument according to a first embodiment of the present invention; [Figure 2] 1 is another perspective view of the handheld medical instrument according to the first embodiment of the present invention; FIG. [Figure 3]1 is a partial longitudinal cross-sectional view showing a motor handpiece of a handheld medical instrument according to a first embodiment. [Figure 4] 1 is a cross-sectional view of a motor handpiece of a handheld medical instrument according to a first embodiment. [Figure 5] 1 is a partial longitudinal cross-sectional view showing a state in which the distal end of a handheld medical instrument according to a first embodiment has a straight shaft shape. [Figure 6] 1 is a partial longitudinal cross-sectional view of a first embodiment of a handheld medical instrument, showing the distal end thereof in the form of an angled shaft. FIG. [Figure 7] 1 is a partial longitudinal cross-sectional view showing the distal end of the handheld medical instrument according to the first embodiment in an open state; FIG. [Figure 8] 1 is a perspective view of a motor handpiece of a handheld medical instrument according to a first embodiment. FIG. [Figure 9] 1 is a partial longitudinal cross-sectional view showing a motor handpiece of a handheld medical instrument according to a first embodiment. [Figure 10] FIG. 10 is a partially cutaway perspective view of a handheld medical instrument according to a modified example of the first embodiment. [Figure 11] FIG. 10 is a detailed view of a sliding movement link of a handheld medical instrument according to a modified example of the first embodiment. [Figure 12] 1 is a perspective view showing an operating state of a handheld medical instrument according to a first embodiment. FIG. [Figure 13] 1 is a perspective view showing an operating state of a handheld medical instrument according to a first embodiment. FIG. [Figure 14] FIG. 10 is a perspective view showing a motor handpiece of a handheld medical instrument according to a second embodiment. [Figure 15] FIG. 10 is a longitudinal cross-sectional view showing a handheld medical instrument according to a second embodiment. [Figure 16] 1 shows a cross-sectional view of a medical handheld instrument according to a second embodiment.

[0030] These figures are schematic in nature and are provided solely for the purpose of understanding the disclosure. Identical elements are designated by the same reference numerals. Features of the various implementations are interchangeable. DETAILED DESCRIPTION OF THE INVENTION

[0031] FIG. 1 shows a perspective view of a medical handheld instrument 1 according to a first embodiment of the present invention. The medical handheld instrument 1 has a medical motor handpiece 2. The motor handpiece 2 has a proximal handle portion 4. As shown schematically in FIG. 1, the handle portion 4 may be coupled to a drive unit 6. Alternatively, the drive unit 6 may be housed within the motor handpiece 2 and may be supplied with energy via a power connection.

[0032] Furthermore, the handheld instrument 1 has a distal tool (end effector, effector section) 8. The tool 8 can be coupled to and detached from the motor handpiece 2 (particularly the handle portion 4) via a shaft (tool shaft) 10. The tool 8 can be configured as, for example, a milling cutter, a drill, or an abrasive head.

[0033] When the shaft 10 is coupled to the handle portion 4, torque is transmitted from the drive unit 6 to the tool 8 via a torque transmission cable disposed within the handheld instrument 1 (particularly the handle portion 4 and the shaft 10), causing the tool 8 to rotate. When the handheld instrument 1 is used in a surgical or medical procedure, it is known that the tool 8 may be angled relative to the shaft 10 (as shown by arrow C in FIG. 1 ). In other words, the tool 8 and the shaft 10 may be angled (tilted) relative to each other such that the longitudinal axis S1 of the tool 8 and the longitudinal axis S2 of the shaft 10 form an angle not equal to 180° (particularly an angle less than 180°), as will be explained in more detail below (see FIG. 6 ).

[0034] For this purpose, as shown in Fig. 1, the handheld instrument 1 according to the present invention is provided with a sleeve-shaped operating element 12. The operating element 12 is arranged at the distal end of the handle portion 4. The operating element 12 is rotatable about the handle longitudinal axis in a first rotation direction A and in a second rotation direction B opposite to the first rotation direction A. In other words, the motor handpiece 2 has a handle portion 4 and an operating element 12 arranged distally thereto. The handle portion 4 and the operating element 12 are arranged coaxially with each other, and the operating element 12 is rotatable relative to the handle portion 4.

[0035] 1, by rotating the operating element 12 in a first rotation direction A from a neutral position (zero position) (where the tool 8 is not angled relative to the shaft 10), the tool 8 is angled relative to the shaft 10. In the handheld instrument 1 according to the present invention, the first rotation direction A is defined as a counterclockwise rotation direction of the operating element 12 relative to the handle portion 4. In other words, the first rotation direction A corresponds to a clockwise rotation direction of the operating element 12 in a plan view of the tool 8 as seen from the distal side.

[0036] As shown in FIG. 2 , the operating element 12 of the handheld instrument 1 according to the present invention can also be rotated relative to the handle 4 in a second rotational direction B, which is opposite to the first rotational direction A. In other words, the second rotational direction B is defined as a clockwise rotation of the operating element 12 relative to the handle 4, or a counterclockwise rotation of the operating element 12 in a plan view of the tool 8 from the distal end. As shown by arrow D in FIG. 2 , rotating the operating element 12 in the second rotational direction B decouples the tool 8 from the shaft 10. This allows for easy and quick tool 8 replacement by rotating the operating element 12 in the second rotational direction B, as will be described in more detail below.

[0037] 3 and 4 show partial cross-sectional views of the handheld instrument 1 according to the first embodiment. An adjusting pin 14 is arranged along the radial direction of the operating element 12 to transmit the rotational movement of the operating element 12 to the shaft 10. The radially outer end of the adjusting pin 14 is received in an axial groove 16 formed on the inner circumferential surface of the operating element 12. The radially inner end of the adjusting pin 14 is received in a rotation transmission sleeve 18. The rotation transmission sleeve 18 is non-rotatably connected to the shaft 10. As a result, when the adjusting pin 14 moves in the circumferential direction, the rotation transmission sleeve 18 and the tool 8 rotate. In other words, when the operating element 12 rotates in the first rotation direction A or the second rotation direction B, the adjusting pin 14 moves in the axial groove 16 together with the operating element 12, and angle (tilt) or eject the tool 8 depending on the rotation direction.

[0038] FIG. 5 shows a longitudinal cross section of the distal end of the handheld instrument 1 when the instrument has a straight shaft configuration. In this state, the operating element 12 is not rotated relative to the handle portion 4 (zero position). As a result, the tool 8 and the shaft 10 are not angled (tilted) relative to each other, and the longitudinal axis S1 of the tool 8 is collinear with the longitudinal axis S2 of the shaft 10. As shown in FIG. 5, the shaft 10 has a proximal shaft portion 20 and a distal shaft portion 22. The proximal shaft portion 20 faces the handle portion 4 and can be coupled to the handle portion 4. The distal shaft portion 22 can be coupled to the tool 8. When the operating element 12 is not rotated relative to the handle portion 4 and the shaft 10 has a straight shaft configuration, the proximal shaft portion 20 and the distal shaft portion 22 are aligned, i.e., at an angle of 0° relative to each other. The proximal shaft 20 is substantially tubular and has an angled end face 24 at its distal end relative to the longitudinal axis S2 of the shaft 10. The distal shaft 22 is also generally tubular. The distal shaft 22 tapers toward its distal end. The distal shaft 22 has an angled end face 26 at its proximal end relative to the longitudinal axis S2 of the shaft 10.

[0039] Each of the angled end faces (inclined end faces) 24, 26 preferably has an angle (action angle) of 22.5° with respect to a plane perpendicular to the longitudinal axis S2 of the shaft 10. When the shaft 10 is extended to have a straight shaft shape, the two inclined end faces 24, 26 are offset from each other so that the edge of the inclined end face 24 located at the longitudinal tip of the proximal shaft portion 20 and the edge of the inclined end face 26 located at the longitudinal tip of the distal shaft portion 22 are positioned on opposite sides of the longitudinal axis S2. The inclined end faces 24, 26 overlap each other. The inclined end faces 24, 26 do not necessarily have to have an angle (action angle) of 22.5°, but may have an angle (action angle) of, for example, 10°, 18°, 30°, 45°, or any other angle (action angle).

[0040] As previously mentioned, the distal shaft 22 is configured to be coupled to the tool 8. That is, the distal shaft 22 is a tool holder that receives the tool 8. The tool 8 is rotatable relative to the tool holder, i.e., the distal shaft 22.

[0041] For this purpose, a first coupling device 28 is arranged in the distal shaft 22. A second coupling device 30 is provided on the tool 8. In the coupled state, the second coupling device 30 realizes the coupling of the tool 8 with the distal shaft 22 by interacting with the first coupling device 28 to fix the tool 8 to the distal shaft 22 in the axial direction A.

[0042] As mentioned above, the longitudinal axis S1 (the longitudinal axis of the distal shaft portion 22) and the longitudinal axis S2 (the longitudinal axis of the proximal shaft portion 20) of the tool 8 form an angle of 0° in the state shown in FIG. 5 . Furthermore, FIG. 5 shows the coupled state of the tool 8 and the distal shaft portion 22. This means that the first coupling device 28 provided on the distal shaft portion 22 and the second coupling device 30 provided on the tool 8 are engaged or interacting with each other. The tool 8 has a tool head (effector) 32 (e.g., a milling head, etc.) and a tool shaft 34. The tool head 32 and the tool shaft 34 are connected to each other so as not to rotate.

[0043] FIG. 5 also shows that the tool shaft 34 is rotatably mounted to the distal shaft portion 22 via a bearing unit 36 (e.g., a rolling bearing unit). A drive shaft 38 extends through the proximal shaft portion 20 and is non-rotatably connected to the tool shaft 34. The drive shaft 38 applies torque from the drive unit 6 to the tool shaft 34 in the form of a torque transmission cable. As a result of this application of torque, the tool shaft 34 rotates relative to the distal shaft portion 22. The bearing unit 36 has at least one bearing 40 (two in this embodiment). These bearings 40 are spaced apart from one another in the axial direction A. The bearings 40 are configured as rolling bearings (more specifically, ball bearings), but may alternatively be configured as plain bearings. The bearings 40 are housed in a bearing housing 42 that is part of the bearing unit 36.

[0044] The second coupling device 30 is inserted into the bearing housing 42 and is therefore not directly mounted on the tool 8. The bearing unit 36, and therefore also the bearing housing 42, is fixed to the tool shaft 34 in the axial direction A. However, alternatively, the second coupling device 30 may be directly mounted on the tool shaft 34. The second coupling device 30 is configured as an axial locking groove 44 that extends continuously in the circumferential direction of the bearing housing 42. The axial locking groove 44 preferably has a semicircular or arc-shaped cross section.

[0045] The first coupling device 28 provided on the distal shaft portion 22 has at least one locking ball 46. The diameter of the locking ball 46 is selected so that the locking ball 46 can be received in the axial locking groove 44. Preferably, the axial locking groove 44 completely surrounds at least a portion of the locking ball 46 that contacts the axial locking groove 44. In the coupled state, the locking ball 46 is held in the axial locking groove 44 by the distal end of a plunger pin (slider) 48 that faces the axial locking groove 44. The plunger pin 48 is part of the first coupling device 28. The plunger pin 48 is fixed in the radial direction R. The plunger pin 48 is axially displaceable or movable within the distal shaft portion 22.

[0046] 5 , the locking ball 46 is received in the axial locking groove 44 and is radially held in the axial locking groove 44 by the plunger pin 48. This position of the plunger pin 48 in the axial direction A is called the coupled position. The edge (periphery) 63 at the distal end of the proximal shaft portion 20 prevents the plunger pin 48 from moving axially toward the proximal shaft portion 20.

[0047] The proximal shaft portion 20 has a fixed outer tube 50, a hollow wheel 52 with internal teeth 54, a pinion 56 with external teeth 58, and an eccentric locking sleeve 60. The hollow wheel 52 is arranged inside the outer tube 50, and the longitudinal axis of the outer tube 50 coincides with the longitudinal axis of the hollow wheel 52. The outer tube 50 and the hollow wheel 52 are thus arranged concentrically. The hollow wheel 52 is connected to the rotation transmission sleeve 18, i.e., the operating element 12, via a hollow shaft 62 housed in the proximal shaft portion 20.

[0048] As mentioned above, the outer tube 50 is designed as a fixed tube and therefore does not move. The distal end of the outer tube 50 has an angled end face 24. The distal end of the outer tube 50 also has a receiving hole 64 and a receiving pin for a bearing 66. The outer tube 50 has a notch (groove) for the ball of the bearing 66. The distal shaft portion 22 is mounted on the bearing 66.

[0049] The internal teeth 54 mesh with the external teeth 58 of the pinion 56. As a result, the rotation of the hollow wheel 52, controlled by the operating element 12, is transmitted to the pinion 56. The pinion 56 rotates in the same direction as the hollow wheel 52. The pinion 56 is driven by the hollow wheel 52, but rotates within an eccentric locking sleeve 60. The eccentric locking sleeve 60 is eccentrically disposed relative to the hollow wheel 52. That is, the longitudinal axis of the eccentric locking sleeve 60 is parallel to the longitudinal axis of the hollow wheel 52, but the longitudinal axes are offset from each other without overlapping. The distal shaft 22 includes an adjustment bushing 68. The adjustment bushing 68 is mounted in a receiving hole 64 in the proximal shaft 20. The adjustment bushing 68 is connected to the pinion 56 via a flexible silicone hose 70. This transmits the rotation of the pinion 56 to the adjusting bushing 68. For this purpose, a silicone hose 70 is attached to the adjusting bushing 68 and the pinion 56, for example by welding or gluing. The adjusting bushing 68 is connected in a fitted manner to the distal shaft portion 22 via a driven pivot (not shown). This transmits the rotation of the adjusting bushing 68 to the distal shaft portion 22.

[0050] FIG. 6 shows a longitudinal cross section of the distal end of the shaft 10. In the position shown in FIG. 6, the distal shaft portion 22 is angled 45° relative to the proximal shaft portion 20, with the two beveled end faces 24, 26 each at an angle (working angle) of 22.5°. Compared to the position shown in FIG. 5, the distal shaft portion 22 has been rotated 180° about its longitudinal axis S1. In the position shown in FIG. 6, the beveled end faces 24, 26 are again completely overlapping (flat). However, due to the rotation of the distal shaft portion 22, the edge of the beveled end face 24 located at the longitudinal end of the proximal shaft portion 20 and the edge of the beveled end face 26 located at the longitudinal end of the distal shaft portion 22 are positioned adjacent to each other. This causes the angles (working angles) of the two beveled end faces 24, 26 to be additive. As a result, the distal shaft portion 22 is angled relative to the proximal shaft portion 20 by twice the angle (working angle) of the beveled end faces 24, 26.

[0051] In the position shown in Figure 6, the driven pivot is located on the opposite side of the eccentric locking sleeve 60. This means that the adjusting bushing 68 rotates 180° from the extended position to the maximum angle position (maximum tilt position). The 45° position represents the reversal point in this design. In this position, the adjusting bushing 68 has rotated 180°. Further rotation of the hollow wheel 52, i.e., the operating element 12, will return the distal shaft portion 22 to its initial position (zero position).

[0052] 6, even when the distal shaft portion 22 is angled to its maximum angular position (maximum adjustment angular position) relative to the proximal shaft portion 20, the locking ball 46 is retained in the axial locking groove 44 by the plunger pin 48 in the radial direction R. Thus, even in this angular position, the tool 8 is secured within the distal shaft portion 22 in the axial direction A by the engagement of the first coupling device 28 and the second coupling device 30.

[0053] The torque transmission path toward the tool shaft 34 (particularly the drive shaft 38) is disposed in a transition region between the distal shaft portion 22 and the proximal shaft portion 20 and is flexible. This flexible portion of the torque transmission path allows the distal portion of the tool shaft 34, including the tool head 32, together with the distal shaft portion 22, to be angled relative to the torque transmission path at the proximal shaft portion 20. At the same time, this flexible portion of the torque transmission path is configured to continue transmitting torque acting on the proximal portion of the tool shaft 34 to the tool head 32.

[0054] FIG. 7 is a longitudinal cross-sectional view of the distal end of the shaft 10 in a disengaged state between the tool 8 and the distal shaft portion 22. That is, in the position shown in FIG. 7, the first coupling device 28 and the second coupling device 30 are not operatively engaged with one another, allowing the tool 8 to be removed or replaced. To disengage the first coupling device 28 and the second coupling device 30, the operating element 12 is rotated in a second rotational direction B (see FIG. 2). As will be explained in more detail below, the locking ball 46 is no longer received in the axial locking groove 44. Instead, the locking ball 46 is held in a radial direction R against the outer circumferential surface of the bearing housing 42 by the plunger pin 48.

[0055] For the locking ball 46 to move from the engaged state shown in FIG. 5 to the disengaged state from the axial locking groove 44, the plunger pin 48 must move in the axial direction A toward the proximal shaft portion 20. In the engaged state, this movement of the plunger pin 48 is blocked by the circumferential edge 63 of the proximal shaft portion 20. However, the circumferential edge 63 is interrupted at a point corresponding to the plunger pin receiving recess 72. When the operating element 12 is rotated in a second rotational direction B, the distal shaft portion 22 rotates in a direction opposite to the angulation direction relative to the proximal shaft portion 20. This rotation of the distal shaft portion 22 is performed, for example, 18° (−18°), until the plunger pin 48 is positioned relative to the proximal shaft portion 20 so as to be aligned with the plunger pin receiving recess 72 in the circumferential direction. A pretensioning element 74, which is part of the first coupling device 28, presses the plunger pin 48 in the axial direction A toward the proximal shaft portion 20. This causes the pretensioning element 74 to press the plunger pin 48 (more specifically, the proximal end of the plunger pin 48 configured as a latching projection 76) into the plunger pin receiving recess 72. The position of the plunger pin 48 when the latching projection 76 engages the plunger pin receiving recess 72 is referred to as the released state or position.

[0056] In the released position, the distal end of the plunger pin 48 no longer faces the axial locking groove 44. This means that the locking ball 46 is no longer held in the axial locking groove 44 in the radial direction R. Therefore, the tool 8 is no longer fixed relative to the distal shaft portion 22 in the axial direction A. Starting from the coupled state, when a pulling force (in the axial direction A) is applied to the distal end of the tool 8, the locking ball 46 is released from the axial locking groove 44. In this way, the tool 8 can be separated from the distal shaft portion 22.

[0057] FIG. 8 shows a perspective view of the distal end of the motor handpiece 2 according to the first embodiment. In the state shown in FIG. 8, the shaft 10 is not coupled to the handle portion 4. As described above, when the operating element 12 is rotated in a first rotational direction A, the tool 8 is angled (tilted), and when the operating element 12 is rotated in a second rotational direction B, the operative engagement between the first coupling device 28 and the second coupling device 30 is released, thereby disengaging the tool 8 from the shaft 10 (or the distal shaft portion 22). To facilitate operation, the operating element 12 is provided with an arrow-shaped indicator 78 indicating the direction of rotation. In combination with the indicator 78 on an indicator sleeve 80 rotatably fixed to the handle portion 4 distal to the operating element 12, the user can immediately recognize which rotational direction corresponds to which function during operation of the handheld instrument 1. For this purpose, as shown in Fig. 8, various angular positions are applied to the outer circumferential surface of the indicator sleeve 80, each corresponding to a predetermined rotation of the operating element 12 in the first rotation direction A (specifically, a predetermined angle (inclination) of the tool 8 relative to the shaft 10 and a lock or unlock symbol). A user can assign a corresponding function (i.e., an angle function (bending function) or a decoupling function (separation function)) to each of the first rotation direction A and the second rotation direction B. The combination of the motor handpiece 2 and the operating element 12 allows intuitive operation and integration of the two functions.

[0058] As shown in Fig. 8, a lock slide 82 is disposed in the motor handpiece 2 according to the first embodiment. The lock slide 82 is housed within the operating element 12 and fixed in the radial and circumferential directions so as to be movable only axially relative to the operating element 12. The lock slide 82 is movable axially relative to the operating element 12 between a (distal) locked position and a (proximal) released position. In the locked position, the operating element 12 is unable to rotate relative to the handle portion 4, as will be described in more detail below.

[0059] For this purpose, in the locked position, as shown in FIG. 9 , a pin portion 83 on the distal side of the locking slide 82 engages with a locking ring 84 housed in the indicator sleeve 80. The locking ring 84 has a number of recesses distributed around the circumference, into which the pin portion 83 extends in the locked position. This circumferentially fixes or holds the operating element 12 relative to the handle portion 4. The recesses in the locking ring 84 preferably correspond to the indicators 78 attached to the outer circumferential surface of the indicator sleeve 80. This makes it easier for the user to angle the tool 8 at a predetermined angle and then fix the tool 8 at that angle.

[0060] Therefore, in order to be able to rotate the operating element 12 relative to the handle portion 4 to adjust the angle or release the clutch, the lock slide 82 must be moved from the locked position to the released position (i.e., in the proximal direction).

[0061] In the motor handpiece 2 according to the first embodiment, the lock slide 82 is axially biased relative to the operating element 12 via a spring element 86. The spring element 86 is disposed between the lock slide 82 and a stop surface of the operating element 12. This causes the spring element 86 to urge the lock slide 82 toward the locked position (i.e., distally). This causes the spring element 86 to exert an automatic restoring force on the lock slide 82 to hold it in the locked position.

[0062] However, it should be understood that the motor handpiece 2 does not necessarily have to include the spring element 86. In a motor handpiece with a manual reset according to this modification of the first embodiment, the user must actively pull the locking slide 82 proximally to unlock it and push it distally to lock it.

[0063] As shown in Figures 10 and 11, the motor handpiece 2 according to the modified example of the first embodiment is provided with an additional ball pressure element 88. The ball pressure element 88 has a spring element 90. The spring element 90 urges the ball 92 proximally against a sliding operation link (latch ring, lock ring) 94 (see Figure 11) firmly held in the handle portion 4. The sliding operation link 94 is provided with a plurality of dome-shaped latch recesses (lock recesses) 96. The latch recesses 96 can at least partially accommodate the balls 92.

[0064] Similar to the recesses in the locking ring 84, the latch recesses 96 are positioned to correspond to the predetermined angles at which the tool 8 can be angled relative to the shaft 10 when the operating element 12 is rotated through the predetermined angle. That is, when the operating element 12 is rotated through the predetermined angle relative to the handle portion 4, the biasing force (elastic force) of the spring element 90 causes the ball pressure element 88 to rotate with the operating element 12 until a predetermined angle is reached at which the ball 92 engages with the corresponding latch recess 96 in the sliding operating link 94. The additional ball pressure element 88 thus provides tactile feedback to the user when adjusting the angle.

[0065] 12 shows the handheld instrument (medical handpiece) 1 according to the first embodiment in an operating state in which the motor handpiece 2 is connected to the drive unit 6. For this purpose, as mentioned above, the motor handpiece 2 has at its proximal end a connection that can accommodate the motor cable 98, as shown in FIG. 12. The motor handpiece 2 also comprises a stop slider 100. The stop slider 100 can be moved proximally in the OFF position (see FIG. 13) to release the connection between the shaft 10 and the motor handpiece 2.

[0066] 13, the stop slider 100 has a locking bolt 102 which is connected to the operating element 12. When the tool 8 is unlocked by rotating the operating element 12 in the second rotational direction B, i.e., when the operative engagement between the first coupling device 28 and the second coupling device 30 is released, the locking bolt 102 extends in the proximal direction.

[0067] When the medical handpiece 1 is in operation, such proximal extension of the locking bolt 102 is not possible because it is blocked by the motor cable 98 (particularly the protrusion of the motor cable 98). This prevents the tool 8 from being ejected during operation if the operating element 12 is accidentally rotated in the second rotation direction B. However, it is still possible to rotate the operating element 12 in the first rotation direction A, thereby allowing the tool 8 to be angled relative to the shaft 10 during operation.

[0068] Fig. 14 shows a motor handpiece 2 for a medical handheld instrument 1 according to a second embodiment. As shown in Fig. 14, the motor handpiece 2 according to the second embodiment does not include a lock slide 82. Omission of the lock slide 82 improves visibility of the surgical field, allows for more intuitive operation, and reduces the effort required for cleaning.

[0069] In order to provide some degree of protection against unintentional rotation of the operating element 12 even without the lock slide 82, and to enable the operating element 12 to be locked at a predetermined angle, two ball pressure elements 104 are arranged on the operating element 12, as shown in FIG. 15. Each ball pressure element 104 has a spring element 106. The spring elements 106 press a ball 108 as a latch body against the lock ring (latch plate) 84. That is, the spring elements 106 press the ball 108 distally against the lock ring 84. The lock ring 84 has a recess into which the ball 108 latches, as shown in FIG. 16.

[0070] As mentioned above, the ball pressure elements 104 press with their distal end (i.e., ball 108) against the locking ring 84. At their proximal end, each ball pressure element 104 has spring load adjustment means in the form of a set screw (grub screw, setscrew) 110. By screwing in the set screw 110, the biasing force (prestress) of the spring element 106, i.e., the spring load (elastic force) acting on the locking ring 84, can be adjusted. The higher the spring load, the less likely it is that the operating element 12 will be rotated (twisted) incorrectly, and the lower the spring load, the easier the angular adjustment, which allows for one-handed operation. [Explanation of symbols]

[0071] 1 Handheld Instrument 2 Motor Handpiece 4 Handle 6 Drive Unit 8 Tools 10 shaft 12 Operating Elements 14 Adjustment pin 16 Axial groove 18 Rotation transmission sleeve 20 Proximal shaft 22 Distal shaft 24,26 Slanted end face 28 First coupling device 30 Second coupling device 32 Tool Head (Effector) 34 Tool shaft 36 Rolling bearing unit 38 Drive shaft 40 Rolling bearings 42 Bearing housing 44 Axial lock groove 46 Rock Ball 48 plunger pin 50 outer tube 52 Hollow Wheel 54 Inner teeth 56 Pinion 58 Outer teeth 60 Lock Sleeve 62 Hollow shaft 63 Edge of proximal shaft 64 Receiving hole 66 Rolling bearings 68 Adjusting bushing 70 Silicone Hose 72 Plunger pin receiving recess 74 Pretensioning element 76 Latch protrusion 78 Indicators 80 Indicator sleeve 82 Rock Slide 83 Pin section 84 Lock ring 86 Spring Elements 88 Ball Pressure Element 90 Spring Elements 92 balls 94 Slide operation link (latch ring) 96 Latch recess 98 Motor Cable 100 stop slider 102 Rock Bolt 104 Ball Pressure Element 106 Spring Elements 108 balls 110 Set screw

Claims

1. A medical motor handpiece (2) for driving a distal end effector (8, 22), comprising: A handle portion (4) is provided, further comprising a preferably sleeve-shaped operating element (12), The operating element (12) is held at the distal end of the handle portion (4) so as to be rotatable about the handle longitudinal axis; the operating element (12) is connectable to the end effector (8, 22) in such a way that a rotational movement of the operating element (12) in a first rotational direction is converted into a movement of the end effector (8, 22) and that a function is imparted to the end effector (8, 22) when the operating element (12) is rotated in a second rotational direction opposite to the first rotational direction, Medical motor handpiece.

2. The motor handpiece (2) is connectable to the end effector (8, 22) via a shaft (10, 20); During the rotational movement of the operating element (12) in the first rotational direction, the operating element (12) angles the end effector (8, 22) relative to the shaft (10, 20).

2. The medical motor handpiece according to claim 1.

3. The end effector (8, 22) comprises a first coupling device (28); The shaft (10, 20) is provided with a second coupling device (30), the first coupling device (28) and the second coupling device (30) operatively engage one another in a coupled state; Rotational movement of the operating element (12) in the second rotational direction disengages the operative engagement between the first coupling device (28) and the second coupling device (30).

3. The medical motor handpiece according to claim 1 or 2.

4. at least one latch and / or stop unit, in particular in the form of a ball pressure element (88, 104), is provided and configured to limit the rotational movement of the operating element (12) in both end rotational positions and / or to increase the resistance to the rotational movement of the operating element (12) in at least one intermediate rotational position; 4. The medical motor handpiece according to claim 1, wherein the motor handpiece is a medical motor.

5. A lock unit (82) is provided, the locking unit (82) in a locked position locks the rotational movement of the operating element (12) in the first rotational direction and the second rotational direction, and in a released position unlocks the rotational movement of the operating element (12).

5. The medical motor handpiece according to claim 1, wherein the motor handpiece is a medical motor.

6. said latch unit and / or stop unit being configured in the form of at least one ball pressure element (104), the latch unit and / or stop unit comprises a spring load setting element, preferably in the form of a set screw (110), for infinitely variable adjustment of the spring load of the ball pressure element (104); 5. The medical motor handpiece according to claim 1, wherein the motor handpiece is a medical motor.

7. The motor handpiece (2) is connectable to the end effector (8, 22) via a shaft (10, 20); The shaft (10, 20) is connectable in a rotationally fixed manner to a rotation transmission sleeve (18) of the motor handpiece (2).

7. The medical motor handpiece according to claim 1, wherein the motor handpiece is a medical motor.

8. The operating element (12) transmits its rotational movement to the rotation transmission sleeve (18) via a radial adjustment pin (14).

8. The medical motor handpiece according to claim 7.

9. The motor handpiece (2) a proximal end connection for coupling the motor handpiece (2) to a drive unit (6); a locking unit (100) coupled to the operating element (12) such that rotation of the operating element (12) in the second rotational direction is locked when the motor handpiece (2) is coupled to the drive unit (6).

9. The medical motor handpiece according to claim 1, wherein the motor handpiece is a medical motor.

10. A medical handpiece (2) comprising the medical motor handpiece (2) according to any one of claims 1 to 9 and an end effector (8, 22), The end effector (8, 22) is coupled to the motor handpiece (2) via a shaft (10, 20) to transmit torque from the motor handpiece (2) to the end effector (8, 22). Handheld medical instruments.

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