1. Field
The invention relates to a video endoscope having an adjustable viewing direction, a proximal handgrip and an endoscope shaft having a cladding tube that is connected to the handgrip in a rotationally fixed manner, wherein a prism unit having at least two prisms is connected to the cladding tube distally in the endoscope shaft in a rotationally fixed manner, wherein at least one image sensor is arranged proximally behind the prism unit, wherein at least one distally arranged prism of the prism unit can be rotated to modify a viewing angle about an axis of rotation crosswise to the longitudinal axis of the endoscope shaft, wherein the prism unit and the at least one image sensor are arranged in a hermetic chamber within the cladding tube, which extends out of the endoscope shaft into the handgrip.
2. Prior Art
Endoscopes, and particularly video endoscopes, with which the light from an operative field entering at a distal tip of an endoscope shaft of the endoscope is focused by an optical system onto one or more image sensors, are known in different embodiments. Thus, there are endoscopes with a direct view, a so-called 0° viewing direction, or endoscopes with lateral viewing direction, which have for example a lateral viewing direction of 30°, 45°, 70° or similar deviating from the 0° viewing direction. Here, the named angular degree means the angle between the central viewing axis and the longitudinal axis of the endoscope shaft. Further, there are endoscopes, or respectively video endoscopes, having an adjustable lateral viewing direction, with which the viewing angle, thus the deviation from the direct view, is adjustable.
Along with an adjustment of the viewing angle, thus the deviation from the direct view, the viewing direction, thus the azimuth angle, can also be adjusted about the longitudinal axis of the endoscope shaft, in that the endoscope as a whole is rotated about the longitudinal axis of the endoscope shaft.
Although with sideways viewing endoscopes typically the term “viewing direction” (direction of view, DOV) is used generally, in the following, in the scope of the present patent application and invention, a distinction is made between the “viewing direction”, which is to correspond to the azimuth angle of the rotation of the endoscope about the longitudinal axis of the endoscope shaft, and the “viewing angle”, which is to designate the polar angle, that is, the deviation from the direct view.
With video endoscopes, a change of the viewing direction, thus a rotation about the longitudinal axis of the endoscope shaft, represents a challenge insofar as in this case the image sensor of the video endoscope is also rotated, such that the horizon position or horizon orientation of the represented image changes. This can be corrected electronically, wherein then means for determining the actual horizon position must be present, for example gravity sensors. Another possibility is to mount the image sensor or image sensors rotatably in the video endoscope so that the horizon position can be corrected or maintained by a rotation of the image sensors in the video endoscope.
The European patent application EP 2 369 395 A1 shows an optical system for a video endoscope in which a change of the viewing angle is accomplished in that one prism of a prism unit having three prisms is rotated about a rotation axis that lies perpendicular, or respectively crosswise, to the longitudinal axis of the endoscope shaft. The other two prisms, which, together with the first prism, define the optical path, are not rotated along with the first prism such that the reflection surface of the first prism, which is rotated, is rotated relative to the corresponding reflection surfaces of the second prism. This results in a change of the horizon position of the displayed image. For this purpose, it is proposed in EP 2 369 395 A1 that a rotation of the image sensor should accompany the pivoting of the first prism. To this end, the image sensor is arranged in a rotatable tube. The prism unit is retained at a tube distal to this tube, wherein the two tubes can rotate relative to each other. A flexible section of the endoscope shaft adjoins the rotatable tube with the image sensor.
Based on this prior art, an object of the present invention is to specify a video endoscope having an adjustable viewing direction, with which the horizon position can be maintained during a change of viewing angle and a change of the viewing direction in a simple manner, wherein the video endoscope in addition should be autoclavable.
This object is solved by a video endoscope having an adjustable viewing direction, a proximal handgrip and an endoscope shaft having a cladding tube that is connected to the handgrip in a rotationally fixed manner, wherein a prism unit having at least two prisms is connected to the cladding tube distally in the endoscope shaft in a rotationally fixed manner, wherein at least one image sensor is arranged proximally behind the prism unit, wherein at least one distally arranged prism of the prism unit can be rotated about a rotation axis crosswise to the longitudinal axis of the endoscope shaft to modify a viewing angle, wherein the prism unit and the at least one image sensor are arranged in a hermetic chamber within the cladding tube that extends out of the endoscope shaft into the handgrip, that is further developed in that a first control element, for setting a horizon position of an acquired image, and a second control element, for setting the viewing angle of the rotatable prism, are arranged outside of the hermetic chamber, wherein arranged in the hermetic chamber there is an inner positioning system, which comprises at least one rotational body, which is arranged on a central rotation axis of the endoscope shaft, axially fastened, and rotatable about the longitudinal axis of the endoscope shaft, to the distal tip of which at least one image sensor is fastened, and at least one axially movable translational body, wherein the translational body is connected in a distal end section of the endoscope shaft to a gear mechanism that converts a translational movement of the translational body into a rotation of the at least one rotatable prism, wherein a drive device, which comprises the first control element and the second control element, is comprised and designed to move the rotational body and the translational body, wherein a drive device is designed such that upon actuating the first control element, only the rotational body is rotated, and upon actuating the second control element, the translational body is moved and the rotational body is rotated such that a horizon position of an image formed on the at least one image sensor remains constant.
According to the invention, the change of the viewing direction and the change of the viewing angle are conveyed using a translational body and a rotational body, wherein the translational body is responsible for the change of viewing direction, because during a translation the translational body interacts with the distal prism in the distal end region and causes it to rotate. The rotational body supports the image sensor(s) and is responsible for the rotation thereof with the goal of a constant horizon position of the displayed image.
One or more lenses can also be arranged between the prism unit and the at least one image sensor.
The drive device which is provided with the video endoscope according to the invention synchronizes the rotation of the rotational body and the translation of the translational body such that in each case, with a change of the viewing angle as well as with a change of the viewing direction, thus on the one hand with a change of the viewing angle relative to the longitudinal axis of the endoscope shaft, and on the other hand with a change of the azimuth position, or respectively the azimuth angle, with a rotation about the longitudinal axis, the horizon position of the displayed image is maintained.
This entails a difference between a change of the viewing angle, for which both the translational body and the rotational body are moved, and a change of the viewing direction with which only the rotational body is moved.
Because the image sensor(s) according to the invention are arranged at the distal end of the rotational body, it is no longer necessary to effect a rotation of a cladding tube or a tube section. Therefore it is also possible to reach with a translational body up to the distal end of the endoscope, in the region in which the distal prism is arranged in the prism unit. This was not possible with an arrangement in which the image sensor unit is held in a separate rotatable tube section, without penetrating the hermetic closing of the hermetic chamber by all components therein.
Thus, the video endoscope according to the invention is significantly better suited also for the disinfection procedure using autoclaves, because the sensitive inner positioning system is in the interior of the hermetic chamber and thus is not affected by autoclaves.
The drive device preferably comprises at least one magnetic coupling for transferring a rotation from outside the hermetic chamber to the rotational body. The magnetic coupling comprises at least one external magnet and one internal magnet. The external magnet is formed outside of the hermetic chamber and is connected to the handgrip for example. The magnetic coupling also has another internal magnet ring in the hermetic chamber. The internal magnet ring is connected directly or indirectly to the rotational body such that a rotation of the part, for example the handgrip of the video endoscope, which is connected to the external magnet ring of the magnetic coupling, leads to a corresponding rotation of the rotational body. Thus, a reference system is produced for the position of the image sensor, or respectively image sensors, relative to the video endoscope as such, without limiting the mobility of the image sensor in the video endoscope.
The drive device also advantageously comprises at least one magnetic coupling for transferring an axial movement and/or a rotation about the longitudinal axis of the translational body from outside of the hermetic chamber to the translational body. The corresponding magnetic coupling also has an internal and an external magnet ring, which are each arranged in the hermetic chamber, or respectively outside of the hermetic chamber. The magnetic rings, or respectively pole shoes, are designed such that a force transfer is possible and thus also a movement in the axial and/or circumferential direction as a rotation. Thus, either due to a sliding movement of the external magnet ring the inner magnet ring and with it the translational body are entrained, and thus are slid, or a rotation of the external magnet ring is converted in the interior into a translational movement of the translational body. Likewise, the translational body can also be entrained rotatingly as such.
The magnetic couplings, which can be used alternatively or cumulatively to each other, provide a force transfer in a direct manner from outside of the hermetic chamber into the hermetic chamber without having to penetrate the hermetic chamber for this purpose.
It is further advantageous that an electrically driven motor, which in the active state causes a rotation of the rotational body, is arranged on an internal magnet support of the magnetic coupling acting on the rotational body. The electrically driven motor in this case is located on the internal magnet support, while the rotational body can in turn be rotated with respect to the internal magnet support. As the magnetic coupling rotates, the internal magnet support rotates with it. A further operation of the corresponding control element leads to an activation of the electrically driven motor, for example an electric motor, a linear motor, a piezomotor, an actuator or similarly suitable drive, and leads to a rotation of the rotational body with respect to the internal magnet support. In this manner, the reference frame, which is positioned in the magnetic coupling by the internal magnet support, is effectively separated from the actual rotation of the rotational body for the purpose of horizon tracking. The transfer of the action of the electrically driven motor to the rotational body can occur using gear wheels, a worm gear or similar.
Also advantageously, an electrically driven motor, which in the active state causes an axial movement of the translational body, is arranged on an internal magnet support of the magnetic coupling acting on the translational body. In this case, the magnetic coupling is expediently designed such that only a transfer of the rotation about the longitudinal axis of the translational body is caused. The translational movement is caused by an electrically driven motor, which can be an electric motor, a linear drive, a piezomotor, an actuator or a similarly suitable motor. The transfer can occur using a toothed gear drive, a worm gear or similar.
If advantageously, the two electrically driven motors can be actuated synchronized or are controlled via an electronic control device, then an effective control of both the viewing direction and the viewing angle of the video endoscope is possible while simultaneously maintaining the horizon position of the reproduced image.
Alternatively to an electronic synchronization, preferably and advantageously, a synchronization drive is comprised having a first gear drive part connected to the translational body or integral with the translational body, and having a second gear drive part connected in a rotationally fixed manner to or integral with the rotational body, wherein the second gear drive part comprises a substantially cylindrical body having a circumferential groove forming a section of a helical line or a thread, in which a projecting part or a thread of the first gear drive part engages. The synchronization drive ensures in the case of force applied from a single source of force, for example an electric motor or a mechanically, in particular hand-operated, control element, that the rotation of the rotational body and the translation of the translational body, and thus the desired setting of the viewing direction and the viewing angle, occur while maintaining the horizon position of the reproduced image. Here, neither two electric motors, nor two unsynchronized mechanical sources of force are required. The synchronization occurs using the synchronization drive.
The synchronization drive comprises two gear drive parts, which are in engagement with each other such that a translation of the translational body leads to a rotation of the rotational body, which is moved due to the circumferential groove forming section of a helical line, or respectively the thread, and the corresponding engagement of the first gear drive part.
Advantageously, the second control element is formed as a slide switch or as a lever, which is connected via a conversion means, in particular a gear mechanism or a lever mechanism, to a retainer, which is translationally movable in the axial direction of the endoscope shaft, and in which an external magnet of the axially movable magnetic coupling is mounted. This design outside of the hermetic chamber permits an effective transfer of translational movements into the hermetic chamber via an axially acting magnetic coupling. A conversion of a movement can be realized in a mechanically simple and reliable manner both with a gear drive, and also with a lever mechanism, wherein the reduction provides good control of the setting by the operator.
Preferably the first control element is designed as a rotating wheel, in particular with a contoured periphery, which has a larger radius, at least in sections, particularly in the circumferential direction, than the handgrip. Thus, the rotary wheel can be held fixed during an operation, such that solely by securely holding the rotary wheel as a first control element, the horizon position of the displayed image is always maintained, independently of whether a viewing direction and/or a viewing angle are changed.
In an advantageous further development, the translational body is designed as a translational tube and/or the rotational body is designed as a rotational tube. The design of the translational body as a translational tube and/or the rotational body as a rotational tube allows signal lines to be placed in the interior thereof. In addition, the rotational body for example can be arranged inside the translational body, without contact thereto.
Further characteristics of the invention will become apparent from the description of the embodiments according to the invention together with the claims and the included drawings. Embodiments according to the invention can fulfill individual characteristics or a combination of several characteristics.
The invention is described below, without restricting the general intent of the invention, based on exemplary embodiments in reference to the drawings, whereby we expressly refer to the drawings with regard to the disclosure of all details according to the invention that are not explained in greater detail in the text. The figures show:
In the drawings, the same or similar types of elements and/or parts are provided with the same reference numbers so that a corresponding re-introduction can be omitted.
The viewing window 5 at the distal tip 4 is curved and asymmetrical. Thus, the viewing window 5 is formed to support a variable lateral viewing angle. A change in the viewing direction, thus a change of the azimuth angle about the longitudinal axis of the endoscope shaft 3, is effected by a rotation of the handgrip 2 about the central rotation axis, or respectively longitudinal axis of the endoscope shaft 3. The cladding tube of the endoscope shaft 3 is connected to the handgrip. The prism unit, not shown, at the distal tip 4 is also rotated with a rotation of the handgrip 2.
The handgrip 2 has a rotary wheel 7 formed as a first control element, and a second control element formed as a slide switch 8.
The rotary wheel 7 is held fixed during a rotation of the handgrip 2 for maintaining the horizon position of the displayed image. This has the effect that the image sensor in the interior of the endoscope shaft 3 does not perform the movement.
In order to change the viewing angle, thus the deviation of the viewing direction from the direct view, the slide switch 8 is moved. A distally directed sliding of the slide switch 8 leads, for example, to an increase of the viewing angle; a proximally directed return of the slide switch 8 in this case causes a reduction of the viewing angle up to the direct view. The actuation of the slide switch 8 is accompanied by a rotation of the image sensor, in order to maintain the horizon position of the displayed image even with a rotation of the prism unit.
The first prism 12 can be rotated about the perpendicular axis A in order to adjust the lateral viewing angle. Thereby, the mirrored surfaces 13 and 15 also rotate counter to each other so that the horizon position of the image, that is further guided proximally, is changed during a rotation of the first prism 12 about the axis A. This must be compensated by a rotation of the image sensor or the image sensors.
Figuratively speaking, this rotation of the horizon can be explained as follows. If the prism unit 10 is arranged so that the rotation axis A in
The rotary wheel 7 is arranged rotatable with respect to the handgrip 2. The rotary wheel 7 comprises a magnetic coupling 38, which is formed so that a rotation of the rotary wheel 7 with respect to the handgrip 2, is transferred to an internal magnet ring of the magnetic coupling 38. This internal magnet ring is connected to a magnet support 42 in a rotationally fixed manner. An electric motor 46 that is attached to the magnet support 42, moves, via a gear wheel 50, a gear wheel 54 that is in connection with a groove body 58 having a oblique circumferential groove. The central rotational body 32 is mounted rotatably in the magnet support 42, as are the gear wheel 54 and the groove body 58.
A pin 60 ensures that the translational body 34 runs in the groove of the groove body 58, and thus a rotation of the groove body 58 leads to a translation of the translational body 34. At the same time, the magnet support 42 can be fixed to the rotary wheel 7, whereby a reference is set for the horizon position.
The viewing direction changes due to rotation of the handgrip 2. This influences the position of the distal prism unit, but not the position of the image sensor. In the handgrip 2 there is also a second magnetic coupling 40 with an external magnet ring and an internal magnet, by means of which in addition a rotation can be transferred to a second magnet support 44. A second electric motor 48 is arranged in a rotationally fixed manner on the magnet support 44; the motor in turn, via gear wheels 52 and 56, enables a rotation of the rotational body 32 in the magnet support 44 and the further components. This enables a reference of the horizon position.
A second control element, not shown in
The functioning of the drive device 30 from
A slide control element 82 that is arranged on the handgrip 2, acts axially moving an external ring magnet 79 of a magnetic coupling 78, via a gear drive 84 and a slider 86. Thus, an axial movement is transferred to the internal ring magnet 81 of the magnetic coupling 78, thus into the hermetic chamber 76.
The internal ring magnet 81 is directly connected on one side to the translational body 74 so that an axial movement of the internal ring magnet 81 leads to a translational movement, thus sliding the translational body 74, which corresponds to a corresponding change of the viewing angle. On the other side, the internal ring magnet 79 is distally connected to a toothed rack 90, which has a catch 91 in the distal end region thereof which engages in a groove 89 of a groove support 88. The groove support 88 is a cylindrical body, having a circumferential groove 89 forming sections of helical lines, that is connected to the rotational body 72 in a rotationally fixed manner. A slide movement of the internal magnet ring 81 in the axial direction leads to a movement also of the catch 91, whereby the axially fixed rotational body is displaced in a corresponding rotation. Movement of the slide control element 82 leads therefore to a simultaneous change of the viewing angle, due to sliding of the translational body 74, and to a corresponding rotation of the image sensor, or respectively image sensors, due to a rotation of the rotational body 72.
If the slide control element 82 is not moved, a rotation of the handgrip 2 with respect to the rotary wheel 7 as a first control element still causes a rotation of the distal prism group, while in contrast, the translational body 74 and the rotational body 72 remain stationary and without rotation.
In addition,
The drive device 70 according to the invention having the synchronization drive 71 is located centrally in the central region of the handgrip 2. The handgrip 2 has a slide control element 8 and distally a rotary wheel 7. The rotary wheel 7 is connected to an external magnet 79 of a magnetic coupling 78, by means of which the horizon position of the video endoscope 1 is set. The internal magnet ring 81 of the magnetic coupling 78 is connected distally to a translational body 74 via a push connection 75, which also allows a rotation of the proximal region of the translational body 74 with respect to the distal region. The prism unit 10 can be rotationally decoupled from the magnetic coupling 78 in this manner. A rotational body 72 is rotationally mounted in the interior of the internal magnet ring 81. The rotational body on the distal tip thereof supports a sensor unit 100. The translational body 74 now runs outside of the rotational body 72 with respect to the central longitudinal axis of the endoscope shaft 3.
The rotational body 72 is connected proximally to a groove support 88, while the internal ring magnet 81 is connected proximally to a toothed rack 90 having a catch 91, which engages in a groove of the groove support 88. The groove support 88 is pre-loaded proximally from outside with a spring 92 so that the groove support 88 is axially fixed to the rotational body 72.
The hermetic chamber 76 is proximally hermetically sealed by a hermetic passage, in which contact pins are embedded, with which an electrical connection is possible to the outside of the hermetic chamber 76. The hermetic passage 94 can for example be a cast glass body having contact pins 96 molded therein.
Outside of the hermetic chamber 76 there is a gear drive 84, that on one side is in engagement with the slide control element 8, which is connected via a connection element to a connecting rod 83 having teeth, which by a movement of the slide control element 8 is also pushed in the axial direction of the endoscope shaft 3. The toothing of the connecting rod 83 is in engagement with a first gear wheel of the gear drive 84. The gear drive 84 converts this movement into a translational movement in the axial direction of the external magnet ring 79 of the magnetic coupling 78.
Outside of the groove body 88 there is a toothed rack 90 which has a catch 91, which engages in the groove 152 of the groove body 88. In the distal region, the toothed rack 90 has an inner contour which engages with an outer contour of a proximal push sleeve 156, which is connected axially movable to the internal ring magnet 81 of the magnetic coupling 78. With this, an axial movement of the ring magnet 81 leads to a corresponding axial movement of the proximal push sleeve 156 and the toothed rack 90, wherein the toothed rack 90 and the proximal push sleeve 156 are rotationally decoupled.
Distally, the internal ring magnet 81 is connected to a distal push sleeve 160, which further conducts the axial movement of the internal ring magnet 81 to a prism group, not shown.
In particular, the combination of the groove body 88 and the toothed rack 90 form a synchronization drive 71. In the interior of the rotational body there is a channel 162 in which electrical lines can be placed, for example.
All named characteristics, including those taken from the drawings alone, and individual characteristics, which are disclosed in combination with other characteristics, are considered individually and in combination as essential to the invention. Embodiments according to the invention can be fulfilled through individual characteristics or a combination of several characteristics.
Number | Date | Country | Kind |
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102012202552.9 | Feb 2012 | DE | national |
The present application is a continuation of PCT/EP2013/000413 filed on Feb. 13, 2013, which is based upon and claims the benefit to DE 10 2012 202 552.9 filed on Feb. 20, 2012, the entire contents of each of which are incorporated herein by reference.
Number | Date | Country | |
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Parent | PCT/EP2013/000413 | Feb 2013 | US |
Child | 14462705 | US |