Positioning Arm

Abstract

The present invention relates to a positioning arm (100) for positioning an instrument, device or tool, the positioning arm (100) comprising two or more arm elements (110, 120) pivotally connected to one another about a pivot axis (131) by a central joint (130), one or more of said arm elements (110, 120) comprising a further joint (140, 150) at an end opposite to said central joint (130), the positioning arm (100) comprising a locking mechanism (140, 150) for blocking and releasing said central joint (130) and said one or more further joints (140, 150). It comprises a blocking device (132) which is arranged in the central joint (130) and which performs the blocking and unblocking of the further joints (140, 150) via one or more transmission devices (111, 112; 121, 122) formed on the arm elements (110, 120), said transmission devices (111, 112; 121, 122) being formed by a pair of clamping arms (111, 112; 121, 122) which also form the arm elements (110, 120).

Description

[Technical field]

[0001] The present invention relates to a positioning arm for positioning instruments, in particular medical instruments. However, the positioning arm according to the invention also enables a variety of other instruments, devices or tools to be accurately positioned. These may include, for example, measuring instruments, monitors, microphones, loudspeakers and lighting instruments. Such a positioning arm is also ideally suited for holding containers and equipment in laboratories. [Background technology]

[0002] A wide variety of positioning arms with different requirements for different applications are known from the state of the art. In particular, for example, in the case of positioning arms for positioning medical instruments, very high demands are placed on the stability, reliability and maneuverability of the positioning arm. Therefore, many attempts have been made in the prior art to further develop and improve positioning systems taking these requirements into account.

[0003] For example, from the applicant's patent application DE 10 200 033 33 A1, a positioning arm is known which has a rotating body or swivel joint and two arm elements hinged thereto, where the angle between the two arm elements is arranged to be fixed by a ratchet attached to the rotating body via a coupling, the coupling being provided with a switch which locks the angular position of the arms relative to one another in a desired switch position.

[0004] The positioning arm known from DE 10 200 03 133 A1 offers the advantage that, thanks to the ratchet, it is possible to easily lock, i.e. block, the rotary joint of the positioning arm with a relatively small force. In particular, it is also possible for the ratchet to be easily operated in a sterile environment, for example under a sterile cover foil. In addition to this, the ratchet allows a certain minimum torque to be specified in order for the positioning arm to be securely locked.

[0005] However, the positioning arm known from US Pat. No. 5,999,333 presents the drawback that the operation still depends on the skill of the user. Thus, a residual risk remains during use if the user does not operate the ratchet correctly and the arm becomes misaligned during the surgical procedure. In addition to this, the ergonomics or ease of use is still not optimal. For example, when positioning the positioning arm, the user must simultaneously hold the instrument at the end of the positioning arm and must keep an eye on the surgical field. Such a simultaneous procedure is very difficult for the user, especially since a relatively large force must be applied when locking the arm and the rotary movement when turning the ratchet may oppose the movement of the other hand. Faster operating options are also desirable, since the positioning arm needs to be repositioned many times before, during and after the surgical procedure, i.e. multiple openings and closings are required.

[0006] Another positioning arm is known from DE 10 200 03 133 A1. In this case, the pressure for locking the joint is transmitted to the joint via hydraulically, pneumatically or mechanically adjustable pistons and / or linkages, which requires high closing forces and relatively complex transmission elements.

[0007] Known 3-joint support arms or 3-joint stands consist of a large number of components which are often very delicate and have to withstand very high compressive and bending forces. This makes them expensive to manufacture and very limited in the choice of materials. Hard alloys or special hardened steels have to be used, especially for the pressure elements / pressure rods and joints (possibly with special coatings), since other materials would not withstand. The use of lighter aluminum or plastic materials (for better handling or for use in the X-ray beam or magnetic field of an MRI scanner) is therefore always accompanied by a loss of locking pressure in the joints and a loss of holding force of the arms in the case of well-known 3-joint holding arms or 3-joint stands, which also reduces durability. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] International Publication No. 2017 / 144172 [Patent Document 2] U.S. Pat. No. 1,068,7915 Summary of the Invention [Problem to be solved by the invention]

[0009] Based on the above-mentioned prior art, it is an object of the present invention to provide a positioning arm that eliminates the problems and drawbacks of the systems known from the prior art and has corresponding advantages over them, in particular to provide a positioning arm that is ergonomically advantageous, convenient and allows for rapid operation of the positioning arm. [Means for solving the problem]

[0010] This object is solved by the subject matter of independent claim 1. Further possible embodiments of the invention are set out in particular in the dependent claims. The solution according to the invention provides a positioning arm for positioning an instrument or tool, comprising two or more arm elements connected to each other by a central joint so as to be pivotable about a pivot axis, whereby one or more of the arm elements comprises a further joint at an end opposite the central joint. The positioning arm further comprises a blocking device for blocking and releasing the central joint and the one or more further joints. The blocking device is arranged at the central joint and brings about the blocking and releasing of the further joint via one or more transmission devices formed on or by the arm elements. By arranging the blocking device at the central joint, the actuation takes place in an ergonomically favorable gripping area to the side and above the patient.

[0011] A particularly simply constructed and robust positioning arm according to the invention is characterized in that the transmission device is formed by one or more pairs of clamping arms, particularly preferably by two pairs of clamping arms, each of which comprises a longer lever arm and a shorter gripping arm, which are connectable by means of a blocking device with their rear ends aligned in the area of ​​the central joint, the gripping arms forming part of a further joint. This embodiment requires very low actuation forces, since in addition to the closing force of the blocking device, the clamping arms provide an additional lever transmission between the force application point at the end of the longer lever arm and the force transmission point at the shorter gripping arm.

[0012] An embodiment according to the invention creates an articulated arm with three main joints which, unlike known articulated arms, acts via a sturdy pair of clamps which directly form the arm element, rather than a delicate pressure element inside the arm element which requires additional guidance.

[0013] Preferably, both arm elements are each provided with a further joint, the blocking device being in each case connected to the further joint by a transmission device. The positioning arm is used, inter alia, to reliably, i.e. safely and accurately, position or hold a medical instrument, tool or auxiliary during surgery on a patient, for example, such a reliable positioning of an instrument or tool, such as a needle, hook, tweezers or marker, is essential, inter alia, during neurosurgery or biopsy procedures.

[0014] For example, when the positioning arm is used to position a medical instrument, one of the arm elements is configured to be connected via a further joint to a fixing device for an operating table. The other arm element can be designed to be connected accordingly via a further joint to an instrument holder that is particularly advantageously designed as a universal adapter. Instead of a fixing device for an operating table, the outer end of one of the arm elements can also be provided with a magnetic clamping device for fixing to a metal surface or a screw-on flange plate for temporary or permanent fixing to a wall or carrier.

[0015] According to a first preferred embodiment, the one or more further joints comprise a rotatable clamping body, which is designed as a ball or as a rotating sleeve, the latter being particularly advantageous for the additional mounting of a rotatable ball and thus allowing not only any desired rotation but also virtually any desired swivel angle.

[0016] Whereas known positioning arms comprise many parts with numerous undercuts, bores, blind holes, adhesives, etc. and are therefore difficult to dismantle for sterilization and difficult to access in all areas, the simple and robust design of few parts, where two or more clamping arms can each be manufactured inexpensively as identical parts, and the ease of assembly also allows for safe and efficient sterilization of all parts of the positioning arm.

[0017] In addition to being simple to manufacture and easy to assemble, the positioning arm according to the invention is also characterized by the fact that it is lightweight and yet designed for very reliable fixation with millimetre precision, even with high payloads.The clamping arms used are also very easy to manufacture from plastic, so that the positioning arms they form can be used directly, for example in MRI applications in the radiation field of tubes.

[0018] The blocking device preferably comprises an actuating element, which is displaceable in the axial direction of the central joint and is connected to the actuating device. In simpler embodiments, the actuating device can be formed by a rotating handle connected to a screw thread, by a clamping handle connected to an eccentric, or preferably by a battery-powered electric motor. The blocking by the blocking device is preferably performed electrically, but manual blocking or releasing of the joint may alternatively be possible. For example, the blocking device can be operated without power via a screw thread or an eccentric. In connection with the design of the transmission device by the clamping arms, an additional mechanical transmission is performed between the introduction of the force and the transmission of the force, which can be within a ratio of about 1:2 to 1:10. Due to this additional transmission ratio, only relatively small actuations are required in the blocking device. The electrical energy required to operate the blocking device in the case of motor drive is preferably provided by an accumulator. This eliminates the need for cabling, which can be a source of danger in the operating room.

[0019] The positioning arm according to the invention solves the problem in an excellent way. With both manual and electric actuation devices, the blocking device can be operated very conveniently, easily and quickly. Furthermore, the movement is designed to be at least substantially independent of the available force of the user. Thanks to the additional transmission by the transmission device, the positioning arm can always be locked in a sufficiently stable position even with small forces and will not shift during the operation. Furthermore, the small movement movements of the blocking device allow a very fast operation. A complete locking of the joint of the positioning arm can be achieved within a few seconds.

[0020] Another advantage of a purely mechanically or electrically operated blocking device is its compactness. In recent years, there have been numerous technical developments in electric drives. Alternative known pressure systems acting by compressed air, hydraulics, etc. (see for example US Pat. No. 1,068,7915 mentioned at the outset) are expensive to manufacture, complex to use and maintain and, due to the fluids used, pose risks to the sterile surgical field and to the user that can be avoided by the present invention. In particular with regard to sterility, it is advantageous that electric drives, i.e. motors including associated electronics, are now also available in a manner that allows them to be sterilized, in particular autoclaved. This is particularly relevant for applications where it is not possible to work with sterile cover foils. With regard to sterility, the entire positioning arm according to the present invention is characterized by the fact that its few parts can be completely disassembled very easily and quickly for cleaning and can also be easily reassembled after sterilization.

[0021] In particular, a gradual opening of the individual joints may be desirable to prevent there being only one fully open state in which all joints of the positioning arm move back and forth unstably. By appropriately adjusting and adjusting the actuation paths of the clamping bodies used in the blocking device, the transmission device and the other joints, it is possible to simply determine exactly which of the joints will be fully locked first at the start of the actuation of the blocking device and which will be fully locked last. By using clamping bodies with slightly different diameters or by using spacer washers in the area of ​​the central joint, this order can also be changed later if necessary.

[0022] The further joint preferably comprises a rotatable clamping body. A first advantageous embodiment provides that the further joint with a ball as the clamping body is designed as a ball joint. A ball joint is a joint with a freely rotatable and pivotable ball. The transmission device formed by the clamping arm of the invention is, for example, configured to receive the ball directly between its gripping arms, which are preferably formed with a slightly concave depression like a trough on the inside of their ends, which locks the ball in place when the lever arms are pressed together.

[0023] According to a further advantageous embodiment, the further joint comprises a rotating sleeve, which is rotatably held on the gripping arms of the clamping arms, for example by means of a groove or screwing, and which is locked when the gripping arms are closed. Particularly advantageously, a slotted receptacle consisting of multiple segments is provided in the rotating sleeve at its end remote from the gripping arms for the ball of the ball joint, so that when the gripping arms are unlocked, the rotation of the rotating sleeve, and also the pivoting movement of the ball in the rotating sleeve, provides an additional degree of freedom. When the gripping arms are locked, the rotation of the rotating sleeve is simultaneously prevented and the ball is also firmly locked by pressing the segments of the rotating sleeve together.

[0024] Another advantageous embodiment provides that the clamping body is connected to the connection joint (113; 123) connecting the two clamping arms by a connecting rod, which in this case pulls the clamping body against a trough-shaped seat at the end of the clamping arm when the clamping arm is locked.

[0025] According to an advantageous further development of the invention, the electric blocking device comprises an electric motor with an output shaft aligned perpendicular to the axis of the central joint and connected to the blocking device by a bevel gear drive or a worm gear. In such a design, the advantage lies in a particularly high degree of compactness. The electric blocking device can be arranged on one of the arm elements to save space. Usually, in most applications, only very limited space is available and the best possible access for the surgeon to the operating area is of high relevance. Such a motor-gearbox arrangement, which can also be used in the present invention, has already been described in the applicant's earlier application DE 102020122352 A1 of 26 August 2020, also filed as PCT / EP2021 / 067028 on 22 June 2021, the contents of which to this extent form part of the disclosure content of the present application.

[0026] All of the above advantages can be particularly well used in a positioning arm for positioning medical instruments. Instead of simple medical devices and instruments, the positioning arm can also be used to position a small robot close to the application area, in which case further actuation of one or more instruments, such as a puncture needle, is preferably performed remotely by the robot, which can be moved with several degrees of freedom.

[0027] Further features, advantages and embodiments of the invention will become apparent from the following description taken in conjunction with the drawings. [Brief description of the drawings]

[0028] [Figure 1] A perspective view of a positioning arm according to the invention having two arm elements connected to a central joint, each formed by a pair of clamping arms and each comprising a further external joint, the clamping body of the external joint being formed by rotating a sleeve and a ball received in the sleeve. [Diagram 2]A view showing a variant of FIG. 1 in which the clamping body of the outer joint is formed by a ball and a device in the form of a hook is placed on one of the outer joints on the universal adapter. [Diagram 3] FIG. 3 shows the variant shown in FIG. 2 with a central catch mechanism in the area of ​​the central joint. [Figure 4] FIG. 3 shows the variant shown in FIG. 2 with two distributed catch mechanisms in the area of ​​the central joint. [Diagram 5] FIG. 5 shows a variant of the embodiment of FIGS. 1 to 4, in which the blocking device of the central joint can be actuated by a clamping handle connected to an eccentric instead of a rotating handle. [Figure 6] FIG. 6 shows the variation shown in FIG. 5 with the clamp handles open. [Figure 7] Longitudinal section through the central joint with a rotating handle and two spring elements designed as disc springs. [Figure 8] FIG. 8 shows a variation of FIG. 7 having a clamp handle and a centrally located spring element in the form of a coil spring. [Figure 9] FIG. 2 is a perspective view of four side-by-side clamping arms forming two arm elements, seen from the side of the central joint. [Figure 10] 10 is a perspective view of the clamping arms arranged side by side as shown in FIG. 9, seen from the other joint side. [Figure 11] 11 illustrates a variation of the pinch arm shown in FIGS. 9 and 10 having a separately formed latch element that can be securely connected to the pinch arm. [Figure 12] 3 is a perspective view from below of the variant shown in FIG. 2 with the holder for the hook-shaped tool removed from the universal adapter. [Figure 13] 13 is an enlarged view of the connection between the universal adapter and the holder shown in FIG. 12. [Figure 14] FIG. 2 is an enlarged view of the rotating sleeve shown in FIG. 1 . [Figure 15]FIG. 16 illustrates that different holders for different instruments or tools can be coupled with the universal adapter engaged in FIG. [Figure 16] FIG. 16 illustrates that different holders for different instruments or tools can be coupled with the universal adapter engaged in FIG. [Figure 17] FIG. 16 illustrates that different holders for different instruments or tools can be coupled with the universal adapter engaged in FIG. [Figure 18] A variant of Fig. 1 with a spring element arranged in the area of ​​the central joint and elastically preloading the arm elements. The spring element is designed as an exemplary torsion bar spring, one of the clamping arms in the area of ​​the central joint has been removed to show this. [Figure 19] FIG. 19 shows a variant according to FIG. 18 with the clamping arms shown in full and the sterile sleeve or foil shown in the area of ​​the universal adapter. [Figure 20] FIG. 5 shows a variant of FIG. 4 with motor actuation of the locking device in the area of ​​the central joint. [Figure 21] FIG. 13 shows a modification in which a connecting rod is attached to the clamp body and to the connecting joint of the clamping arms, and one clamping arm is omitted. [Figure 22] FIG. 22 shows a variant according to FIG. 21 having both clamping arms. [Figure 23] FIG. 22 is a first perspective exploded view of the modification example shown in FIG. 21 . [Figure 24] FIG. 23 is a second perspective exploded view of the modification example shown in FIG. 22; [Diagram 25] FIG. 13 shows a positioning arm having a magnetic attachment at the outer end of the first arm element. [Figure 26] FIG. 13 illustrates a positioning arm having a flange plate disposed on an outer end of a first arm element. [Figure 27] FIG. 13 shows a variation having shortened clamping arms. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] Similar elements are generally designated in the figures with the same or similar reference numbers. The positioning arm 100 shown in Figure 1 comprises a first arm element 110 and a second arm element 120 which are connected to each other by a central joint 130. At the end remote from the central joint 130, the first arm element 110 comprises a further joint 140, through which the positioning arm 100 is connectable to a fastening device 160.

[0030] At the end remote from the central joint 130 , the second arm element 120 is provided with a further joint 150 through which the positioning arm 100 is connectable to a universal adaptor 170 .

[0031] The first arm element 110 is formed by an outer clamping arm 111 and an inner clamping arm 112. The outer clamping arm 111 and the inner clamping arm 112 are connected to each other at a connection joint 113 formed, for example, by a bolt 1131. The outer clamping arm 111 comprises a lever arm 1111 starting from the central joint 130 and a gripping arm 1112 between the connection joint 113 and the further joint 140. The inner clamping arm 112 comprises a lever arm 1121 starting from the central joint 130 and a gripping arm 1122 behind the connection joint 113 in the direction of the further joint 140.

[0032] One or more gripping parts 1113 are formed on the gripping arm 1112 and one or more gripping parts 1123 are formed on the gripping arm 1122. The inner side of the gripping arm 1112 is provided with a concave recess 1114 and the inner side of the gripping arm 1122 is provided with a concave recess 1124. The gripping parts 1113 of the gripping arm 1112 and the gripping parts 1123 of the gripping arm 1122 surround a clamping body 141 of a further joint 140, which in FIG. 1 is in the form of a rotating sleeve 143. The rotating sleeve 143 is shown enlarged in FIG. 14. The rotating sleeve 143 is provided with a ring groove 1431 at a distance from its rear end. The rotating sleeve is divided into four segments 1432 by four slits 1433 evenly distributed in the outer shell parallel to the axis. The slits 1433 extend beyond the ring groove 1431. The diameter of the front circular opening of the rotating sleeve 143 is such that the ball 142 can be inserted into the interior of the rotating sleeve 143 by slightly expanding the segment 1432. The interior of the rotating sleeve 143 preferably includes a bulbous shape adapted to the ball 142.

[0033] The ball 142 is connected to a cylindrical connecting piece 144. The connecting piece preferably has external threads (not shown) formed thereon that can be threaded into matching internal threads (also not shown) of a fastening device 160.

[0034] The second arm element 120 is formed by an outer clamping arm 121 and an inner clamping arm 122. The outer clamping arm 121 and the inner clamping arm 122 are pivotally connected to one another at a connecting joint 123 formed, for example, by a bolt 1231. The outer clamping arm 121 comprises a lever arm 1211 starting from the central joint 130 and a gripping arm 1212 between the connecting joint 123 and the further joint 150. The inner clamping arm 122 comprises a lever arm 1222 starting from the central joint 130 and a gripping arm 1222 behind the connecting joint 123 in the direction of the further joint 150.

[0035] One or more gripping parts 1213 are formed on the gripping arm 1212 and one or more gripping parts 1223 are formed on the gripping arm 1222. The inner side of the gripping arm 1212 is provided with a concave recess 1214 and the inner side of the gripping arm 1222 is provided with a concave recess 1224. The gripping parts 1213 of the gripping arm 1212 and the gripping parts 1223 of the gripping arm 1222 surround a clamp body 151 of a further joint 150, which in FIG. 1 is configured in the form of a rotating sleeve 153. The rotating sleeve 153 is shown enlarged in FIG. 14. The rotating sleeve 153 is provided with a ring groove 1531 at a certain distance from its rear end. The rotating sleeve 153 is divided into four segments 1532 by four slits 1533 evenly distributed in the outer wall parallel to the axis. The slits 1533 extend beyond the ring groove 1531. The diameter of the front circular opening of rotating sleeve 153 is such that ball 152 can be inserted into the interior of rotating sleeve 153 by slightly expanding segment 1532. The interior of rotating sleeve 153 preferably includes a bulbous shape adapted to ball 152.

[0036] Ball 152 is connected to a cylindrical connecting piece 154 which preferably includes an external thread (not shown) that can be threaded into a matching internal thread (also not shown) of a carrier 171 of a universal adapter 170.

[0037] 9-11 show the four clamping arms 111, 112, 121 and 122 as individual parts. It can be seen from the illustrations that the four clamping arms 111, 112, 121 and 122 can be manufactured as identical parts as far as possible, which greatly simplifies manufacturing and inventory control. It can further be seen from these figures that the clamping arm 111 comprises a bore 1119 formed as a through bore at its end facing the central joint 130. Similarly, the clamping arm 112 comprises a bore 1129, the clamping arm 121 comprises a bore 1219 and the clamping arm 122 comprises a bore 1229.

[0038] Two or more of the clamping arms 111, 112, 121 and 122 include latch elements 1115, 1125, 1215 and 1225. In Figures 9 and 10, the latch elements 1115, 1125, 1215 and 1225 are formed directly on the clamping arms 111, 112, 121 and 122. The latch elements 1115, 1125, 1215 and 1225 include teeth 1116, 1126, 1216 and 1226, respectively.

[0039] In an alternative embodiment shown in FIG. 11, latch elements 1115, 1125, 1215 and 1225 provided with teeth 1116, 1126, 1216 and 1226 are designed as independent disk-shaped components, each having two bolts 115 on the face opposite the teeth and configured to securely engage corresponding position holes 114 on clamping arms 111, 112, 121 and 122.

[0040] The clamping arms 111, 112, 121 and 122 are provided with an offset shape, and a laterally extending bore is provided approximately in the center of the offset for forming the connection joints 113 and 123, respectively, by means of a through bolt. In these regions of the laterally extending bores, rectangular cutouts 1117, 1127, 1217 and 1227 are formed on the four clamping arms 111, 112, 121 and 122. These cutouts extend approximately to the center of the respective clamping arms and allow the respective pairs of clamping arms 111 to engage with 112 and 121 to engage with 122 in the assembled state.

[0041] The clamping arms 111, 112, 121 and 122 can be inexpensively manufactured as identical parts by sturdy design such as aluminum die casting or plastic injection molding.

[0042] The central joint 130 forms a pivot 131 for the first arm element 110 and the second arm element 120. The central or intermediate joint 130 connects the rear end of the first arm element 110, which is clamped by the outer clamp arm 111 and the inner clamp arm 112, to the rear end of the second arm element 120, which is clamped by the outer clamp arm 121 and the inner clamp arm 122, by a threaded rod 1322 passing through bores 1119, 1129, 1219 and 1229, as best seen in FIG.

[0043] In each case the outer clamping arm 121 of the second arm element 120, the inner clamping arm 112 of the first arm element 110, the inner clamping arm 122 of the second arm element 120 and the outer clamping arm 111 of the first arm element 110 are located one above the other, alternating from bottom to top. A threaded rod 1322 is connected at its upper end to an operating element formed as a rotating handle 1321 or as shown in figures 5, 6 and 8 as a clamping handle 1324 provided with an eccentric 1325.

[0044] The lower end of the threaded rod 1322 is either screwed into a nut 1323, as shown in FIG. 7, or directly into the internal threads of the outer clamping arm 121 formed in the area of ​​the bore 1219, as shown in FIG.

[0045] The threaded rod 1322 together with the operating elements, ie the rotating handle 1321, the clamping handle 1324 or the motor 1326 shown in FIG. 20, and the internal threads of the anchoring or clamping arm 121 in the nut 1323 form the blocking device 132.

[0046] The motor 1326 is preferably driven by an accumulator located in a housing preferably integrally formed on the clamping arm 111. The operating element 1327 is ergonomically positioned such that the housing can also be used as a handle in an ergonomic manner when guiding the positioning arm 100 to a desired position, as shown in FIG.

[0047] When the operating elements 1321, 1324 or 1326 are tightened, the ends of the clamping arms 111, 112, 121 and 122 are pressed against each other. When only slightly tightened, pivoting movement about the pivot axis 131 is still possible. On the other hand, when the operating elements 1321, 1324 or 1326 are tightly tightened, the pivoting movement of the arm elements 110 and 120 relative to each other is blocked at the central joint 130.

[0048] This locking can be strengthened by the interlocking teeth 1116, 1126, 1216 and 1226 of the latch elements 1115, 1125, 1215 and 1225. Two variants are possible here. As shown in Fig. 3, in the first variant a central engagement of the two latch elements 1126 and 1226 is possible. This embodiment is preferred when it is desired to block the other joints 140 and 150 before blocking the central joint 130.

[0049] On the other hand, as shown in Figures 4, 5, 6 and 7, the second variant also allows for a distributed engagement in the two pairs of latch elements 1115 and 1225 and 1215 and 1125. In this case, an intermediate position of the spacer sleeve 133 is advantageous. This second variant is preferably used when locking of the central joint 130 is desired before locking of the other joints 140 and 150.

[0050] By blocking the central joint 130 by the blocking device 132, the other joints 140 or 150 are also blocked simultaneously or with a small time delay. When the clamping ends are pressed together at the lever arms 1111, 1121, 1211 and 1221 of the clamping arms 111, 112, 121 and 1222, the gripping arms 1112 and 1122 of the first arm element 110 and the gripping arms 1212 and 1222 of the second arm element 120 are pressed together simultaneously. Thereby, they respectively surround the clamping bodies 141 and 151 formed by the balls 142 and 152, respectively, or by the rotating sleeves 143 and 153, respectively, which according to a particularly advantageous variant are respectively suitable for receiving the balls 142 and 152, respectively.

[0051] By means of balls 142 or 152 of different diameters and / or by means of spacer sleeves 133 of different thicknesses, it is possible to set very precisely which of the joints 130, 140 and / or 150 lock first and which lock last when the blocking device 132 is actuated. According to an advantageous variant, for example, the joint 140 can be blocked first after the positioning arm 100 has been roughly pivoted into the required use position. When the blocking device 132 is tightened further, for example the central joint 130 can be blocked next and the further joint 150 can be blocked last after the instrument 190 arranged on the universal adapter 170 has been rotated or pivoted into the target position. The sequence just described is to be understood only as an example. Any other sequence is also possible with a corresponding adjustment of the diameter of the balls 142 or 152 and / or the rotating sleeves 143 or 153 and / or the thickness of the spacer washer 133. It is also possible to affect the timing of locking of each joint 130, 140 or 150 by varying the length ratio of the lever arm to the gripping arm in each pair of clamping arms.

[0052] Instead of the latch elements 1115, 1125, 1215 and 1225, as shown in FIG. 8, an outer cone 1118 on the clamping arm 111 engaging with an inner cone 1228 on the clamping arm 122, and an outer cone 1218 on the clamping arm 121 engaging with an inner cone 1128 on the clamping arm 112, can also assist the blocking device 132 in blocking the central joint 130.

[0053] To ensure that the blocking device 132 of the central joint 130 opens easily when the rotating handle 1321, the clamping handle 1324 or the motor 1326 are opened, it is advantageous for one or more spring elements 134 to counter the closing forces. In FIG. 8, a helical compression spring surrounding the threaded rod 1322 is arranged in the central region of the threaded rod 1322 as an axial spring element 134 for this purpose. In FIG. 7, two spring elements 134 in the form of disc springs are arranged axially spaced apart from each other between the clamping arms 111 and 122 and between the clamping arms 112 and 121, respectively, surrounding the threaded rod 1322.

[0054] Handling of the positioning arm 100 according to the invention is advantageously further facilitated by the fact that, as shown in Figures 18 and 19, a further spring element 135 is provided by which the first arm element 110 and the second arm element 120 are elastically preloaded in position relative to each other. Advantageously, this is the extended position in which the first arm element 110 and the second arm element 120 subtend an angle of 180°. In the embodiment shown, the further spring element 135 is formed as a torsion leg spring surrounding a threaded rod 1322, the end of which is fixed against a stop 1351 on the clamping arm 112 or a stop 1352 on the clamping arm 122.

[0055] 19, fastening device 160 is configured to be screwed into a holder (not shown) by a screw 163 connected to a rotating handle 162, and can be fastened to, for example, a side rail of a surgical table. Locking teeth 164 are also configured to help securely fix positioning arm 100 in place.

[0056] At the other end on the patient side, a universal adapter 170 is particularly preferably provided adjacent to the second joint 150, which can be connected to the connecting piece 154, for example by screwing the connecting piece 154 into the carrier 171. The universal adapter 170 comprises a molding 173, particularly preferably designed like a three-sided prism. The molding 173 is configured to be securely connected to a receptacle 181 in the holder 180, whereby the molding 173 is pressed wedge-shaped against two inclined front sides of the receptacle 181 when a slider 184 displaceably mounted on the holder 180 is pressed from the rear against the molding 173 by a rotating handle 182. The universal adapter 170 may further comprise a rotation axis 172 formed by a screw 175 on which the rotating handle 174 is arranged (FIG. 19). A locking disk 176 on the carrier 171 and a locking disk 177 on the compact 173 allow the compact 173 to be finely rotated and locked relative to the carrier 171 so that the holder 180 seated on the compact 173 can be correspondingly finely rotated and locked with the tool 190.

[0057] The prisms of the molding 173 have no sharp corners and edges. If a sterile cover foil 200 (see FIG. 19) is placed between them, the foil 200 is not damaged. This ensures that the sterile barrier formed by the cover foil 200 is not breached. At the same time, the prisms of the molding 173 always allow a good, and in particular secure, form-fit (with or without the cover foil 200 in between) and ensure that the position of the instrument 190 attached to the universal adapter 170 does not change.

[0058] As can be seen from figures 15 to 17, the universal adapter 170 is configured to be used to easily and quickly connect a wide variety of tools and instruments 190. In figure 15, the tool 190 is formed by a hook 191. In figure 16, a tool holder 186 is placed on the holder 180, on which, in the example shown, a needle guide 192 for guiding a needle 194 is mounted. In figure 17, the holder 180 comprises, by way of example, a pair of tweezers 195 which can be fixed to the holder 180 by a clamp. The holder 180 is preferably provided with a further rotation axis 185, so that the tool 190 can be rotated relative to the tool holder 186 and locked by a rotation handle 187.

[0059] The universal adaptor 170 represents an independent inventive feature in itself, since it can be connected by its shaped body 173 to any holder 180 for any tool 190, 191, 192, 193, 194 and 195. As a result, any tool 190, 191, 192, 193, 194 and 195 can be arbitrarily arranged on a number of such positioning arms 100 and quickly exchanged as required during surgery. The positioning arm 100 according to the invention is also suitable for mounting a preferably remotely controlled robotic system or a patient positioning system on the universal adaptor 170. The locking of the joints 130, 140, 150 is so stable in the locked state that the entire operating table can be raised on the universal adaptor 170 without any change in the set position of the joints 130, 140, 150.

[0060] As can be seen from Figures 9 to 11, the positioning arm 100 of the present invention has a very small number of clamping arms 111, 112, 121 and 122 that can be easily disassembled and assembled so that disassembly for sterilization is easily possible.

[0061] Sterilization can also be achieved simply by pulling a sterile cover foil 200 over the positioning arm 100. This is only shown in the area of ​​the further joint 150 in Fig. 19. The universal adapter 170 allows this cover 200 to be clamped non-destructively between the molding 173 and the receptacle 181 in the holder 180.

[0062] 21 to 24 show another variant of the clamping arm. In this case the clamp body is formed by a partially hollow ball 1420. In the bore of the ball 1420, which is provided at one end with a thread 1421 and at the other end with slits 1422 arranged crosswise, one end of a connecting rod 1423 having a ball head 1424 is attached. The shaft 1426 of the connecting rod 1423 passes through the slot 1422 and the connecting rod 1423 is supported on the connecting joint 113 or on a bolt 1131 forming the connecting joint by means of a bearing eye 1425 at the other end of the connecting rod 1423 opposite the ball head 1424.

[0063] After the coupling rod 1423 has been inserted into the bore of the ball 1420 , a connecting piece 1440 having a thread 1441 attached to one end is screwed into the thread 1421 of the ball 1420 . When the clamping arms 111 and 112 are pressed together against the recesses 1114 (which in this case are flatter) of the gripping portion 1113 at the ends of the clamping arms 111 and 112, the ball 1420 is pulled by the connecting rod 1423, thereby constraining the movement of the ball 1420. The teeth of the gripping portion 1113 are designed in this variant to be shorter than in the first described variant, in which the teeth of the gripping portions 1113, 1123, 1213, 1223 engage around the clamping bodies 141, 151 or balls 142, 152 by more than half their diameter.

[0064] Figure 25 shows a further fastening option for the positioning arm according to the invention, where the connecting piece 144 of the joint 140 is connected to a magnetic holder 210, which can be set in an active position or inactive by a magnetic switch 212. By means of the magnetic holder 210, this positioning arm can be very easily fixed to a metal surface and released again.

[0065] In FIG. 26, the connecting piece 144 of the joint 140 is connected to a flange plate 220 which is provided with a number of bores 222 for attachment to a carrier or a wall, for example by means of screws.

[0066] FIG. 27 shows a particularly small embodiment of the positioning arms in which the clamping arms 111, 112; 121 and 122 are very short and compact. [Explanation of symbols]

[0067] 100 Positioning Arm 110 (first) arm element 111 (outer) clamping arm of (110) 1111 (111) Lever Arm 1112 (111) Grasping arm 1113 Gripping part 1114 Recess 1115 Latching element 1116 Teeth 1117 Notch 1118 (Outer) Cone 1119 Boa 112 (110) (inner) clamping arm 1121 (112) Lever arm 1122 (112) Grasping arm 1123 Gripping part 1124 Recess 1125 Latching Element 1126 Teeth 1127 Notch 1128 (inner) cone 1129 Boa 113 (111 and 112) Connection joint 1131 Volts 114 Position Hole 115 volts 120 (2nd) arm element 121 (outer) clamping arm of (120) 1211 (121) Lever Arm 1212 (121) Grasping arm 1213 Gripping part 1214 Recess 1215 Latch Element 1216 Teeth 1217 Notch 1218 (Outer) Cone 1219 Boa 122 (120) (inner) clamping arm 1221 (122) Lever arm 1222 (122) Grasping arm 1223 Gripping part 1224 Recess 1225 Latch Element 1226 Teeth 1227 Notch 1228 (inner) cone 1229 Boa 123 (121 and 122) Connection joint 130 (center) joint 131 Swivel Axis 132 block devices 1321 Rotating Handle 1322 Threaded Rod 1323 Nut 1324 Clamp handle 1325 Eccentric 1326 Motor 1327 Operational Elements 133 Spacer washer 134 (Axial) Spring Element 135 Spring elements (torsion springs) 140 (More) Joints 141 Clamp body 142 Ball 1420 Ball (in Figures 21 to 24) 1421 Thread (at 1420) 1422 Slit (at 1420) 1423 Connecting Rod 1424 Ball head (in 1423) 1425 Bearing eye (at 1423) 1426 (1423) Shaft 143 Rotating sleeve 1431 Ring groove 1432 segments 1433 Slit 144 Connection piece 1440 Connection piece (in Figs. 21-24) 1441 Thread (at 1440) 150 (more) joints 151 Clamp body 152 Ball 153 Rotating sleeve 1531 Ring groove 1532 segments 1533 Slit 154 Connection piece 160 Fastening Devices 162 Rotating Handle 163 Screw 164 Locking teeth 170 (Universal) Adapter 171 Career 172 Rotational Axis 173 Molded body 174 Rotating Handle 175 Screw 176 Locking disc (in 171) 177 Locking disc (in 173) 180 Holder 181 Receptacle 182 Rotating Handle 183 Screw 184 Slider 185 Rotational Axis 186 Tool holder 187 Rotating Handle 190 Tools, Equipment 191 Hook 192 Needle guide 193 Tool Carrier 194 needles 195 Tweezers 200 (sterile) cover foil (sleeve) 210 Magnetic holder 212 Magnetic Switch 220 Flange plate 222 bore (in 220)

Claims

1. A positioning arm (100) for positioning an instrument, device or tool, comprising: comprising two or more arm elements (110, 120) pivotally connected to one another by a central joint (130) about a pivot axis (131); one or more of said arm elements (110, 120) comprises a further joint (140, 150) at an end opposite said central joint (130); the positioning arm (100) comprises a blocking device (132) for blocking and releasing the central joint (130) and the one or more further joints (140, 150) of the arm elements (110, 120), The blocking device (132) is arranged in the central joint (130) and performs the blocking and unblocking of the further joints (140, 150) via one or more transmission devices (111, 112; 121, 122) formed in the arm elements (110, 120), the transmission devices (111, 112; 121, 122) being formed by a pair of clamping arms (111, 112; 121, 122) which also simultaneously form the arm elements (110, 120), a positioning arm (100).

2. 2. The positioning arm (100) of claim 1, wherein both arm elements (110, 120) each comprise a further joint (140; 150), and said blocking device (132) comprises a respective transmission device (111, 112; 121, 122) for said further joint (140; 150).

3. 3. The positioning arm (100) according to claim 1 or 2, wherein said further joint (140; 150) comprises a rotatable clamping body (141; 151).

4. 4. The positioning arm (100) according to claim 3, wherein the rotatable clamping body (141; 151) is formed as a ball (142; 152), as a rotating sleeve (143; 153), or as both.

5. The clamping arms (111, 112; 121, 122) each include a lever arm (1111, 1121; 1211, 1221) and a gripping arm (1112, 1122; 1212, 1222), the lever arms (1111, 1121; 1211, 1221) are configured to be connected by the blocking device (132) with their rear ends aligned in the area of ​​the central joint (130), The positioning arm (100) according to any one of the preceding claims, wherein said gripping arms (1112, 1122; 1212, 1222) form part of said further joints (140, 150).

6. A positioning arm (100) as described in any one of claims 1 to 5, wherein the blocking device (132) comprises an actuating element (1322) which is displaceable in the axial direction of the central joint (130) and is connected to actuating devices (1321, 1324, 1326).

7. 7. The positioning arm (100) according to claim 6, wherein the actuation device is formed by a rotating handle (1321), by a clamping handle (1324) connected to an eccentric (1325), or by a motor (1326).

8. A positioning arm (100) according to any one of the preceding claims, wherein one of the further joints (140) is provided with a fastening device (160) suitable for attachment to an operating table and another of the further joints (150) is designed for connection to an adapter (170) suitable for attaching different instruments, devices or tools (190; 191; 192; 193).

9. The positioning arm (100) according to any one of the preceding claims, wherein said clamping arms (111, 112; 121, 122) are constructed as one and the same part.

10. The positioning arm (100) according to any one of the preceding claims, wherein said clamping arms (111, 112; 121, 122) are made of light metal, a light metal alloy or a plastic material.

11. The positioning arm (100) according to any one of the preceding claims, wherein the blocking device (132) comprises a latching element (1125, 1225) arranged or formed on the transmission device (111, 112; 121, 122).

12. 9. The positioning arm (100) of claim 8, wherein the adapter (170) comprises one or more shaped bodies (173) for cooperation with a complementarily shaped receptacle (181) of a holder (180) for the tool, device, or instrument (190; 191; 192; 193).

13. 13. The positioning arm (100) of claim 12, wherein the molded body (173) is configured to be fixed relative to the receptacle (181) by a slider (184) arranged on the holder (180).

14. The positioning arm (100) according to any one of the preceding claims, wherein the blocking device (132) is suitable and arranged for time-delay locking of the central joint (130) and the further joint (140; 150).

15. The positioning arm (100) according to any one of the preceding claims, wherein one or more spring elements (134) are arranged in the area of ​​the central joint (130) which counteract the closing force of the blocking device (132).

16. The positioning arm (100) according to any one of the preceding claims, wherein one or more spring elements (135) are arranged in the region of the central joint (130) for preloading one or more of the arm elements (110; 120) into a predetermined home position.

17. 5. The positioning arm (100) according to claim 3 or 4, wherein the rotatable clamping body (141; 151) is connected by a connecting rod to a connection joint (113; 123) connecting the two clamping arms (111, 112; 121, 122) together.

18. A positioning arm (100) for positioning an instrument or tool, comprising: comprising two or more arm elements (110, 120) pivotally connected to one another by a central joint (130) about a pivot axis (131); one or more of said arm elements (110, 120) comprises a further joint (140, 150) at an end opposite said central joint (130); said positioning arm (100) comprising a front central joint (130) and a blocking device (132) for blocking and releasing said one or more further joints (140, 150); said blocking device (132) being arranged in said central joint (130) and performing said blocking and unblocking of said further joints (140, 150) via one or more transmission devices (111, 112; 121, 122) formed in said arm elements (110, 120); A positioning arm (100), one of said further joints (150) being designed to be connected to a universal adapter (170) suitable for fastening different tools (190; 191; 192; 193).

19. 20. The positioning arm (100) of claim 18, wherein the universal adapter (170) comprises one or more shaped bodies (173) for cooperation with a complementarily shaped receptacle (181) of a holder (180) for the tool or instrument (190; 191; 192; 193).

20. 20. The positioning arm (100) of claim 19, wherein said shaping (173) is in the form of a three-sided prism having rounded corners and edges.

21. The positioning arm (100) according to claim 19 or 20, wherein the shaped body (173) and the receptacle (181) are configured to non-destructively clamp a sterility foil (200) at least partially surrounding the positioning arm (100) or the tool (190; 191; 192; 193).

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