DE102009037030A1 - Tubular shaped shaft for use as gripper for gripping e.g. component in laparoscopic instrument, has bendable areas attached at ends of rigid section, which exhibits bending position, and rods designed in longitudinal movable manner - Google Patents

Abstract

The shaft (1) has bendable areas (4, 5) attached at ends of a rigid section (3). Rods (7, 9) are designed in a longitudinal movable manner and fixed at ends of an end tube (12) that is guided parallel to an axis. Three concentrical pipes are connected together in a slidable manner with narrow tolerances. An outer tube and the inner tube are designed in a bendable manner in the bendable areas without changing circumferential length. A metallic middle tube forms the end tube at ends and divides in an area between other rods. The rigid section exhibits a bending position.

Description

The The invention relates to a shaft in the preamble of the claim 1 mentioned type.

Such shafts are in EP 1 708 609 B1 . US 7,410,483 B2 and US 7,147,650 B2 described.

there The shaft has two bendable areas, which are over along the circumference arranged arranged rods along are. If one bends one of the two bendable areas, then one becomes or several of these rods shortened in this area and others extended in this area. The rods are circumferentially strong and only longitudinally displaceable mounted on the shaft, can So do not dodge. You must be of the bend-operated Range extending through shortening or lengthening the range of bending movements resulting from longitudinal displacement transferred to the other bendable area. Because the rods attached to the ends of axially parallel tailpipes are and thus their length between the tailpipes rigid is predetermined and not corrected by lateral evasion can not be left to the poles, than to shorten in the second bendable area so or to extend that the second bendable area in a forced movement in a different direction than the bending-actuated Area is bent. This results in a shaft with two bendable Areas and an intermediate rigid section. you can hold this shaft on the rigid section and on one of the bend bendable areas in any direction. It bends then forcibly the other area in the reverse bending direction. In this case, then the ends of the two bendable areas are always parallel, so that by pressing the bend-operated Area of the second bendable area very simple and clear is controllable. The shaft may be formed as a hollow tube, in the z. B. surgical work channels, image guides, light guides, Pull cable, electric cables and the like can be laid. At one end of the shank according to the invention can, for example a handle and be arranged at the other end of a forceps jaw.

These However, known constructions are very complicated, expensive and also difficult to use.

The Object of the present invention is therefore a shaft to create a surgical instrument that is due to uncomplicated construction, low costs and simple operation distinguished.

at The construction according to the invention are three tubes inserted into each other, the z. B. formed as a thin metal tubes are. The tubes are slidingly close together, so that the middle Pipe through the inner and outer pipe against Evasive movements to the inside or outside is protected. The middle tube trains the rods, in large ones Number in the perimeter closely juxtaposed so that they are mutually exclusive support and prevent evasion in the circumferential direction. This construction is very simple z. B. plastic pipes or Metal tubes can be produced by cutting, very stiff and for transmission high forces suitable. The operation is simple and the Costs are low. Since the rigid section of the shaft Abwinkelungsstellen has, he can, for. B. in shafts for laparoscopic Pliers that are to be used in close proximity to each other, be beneficial.

Especially advantageous according to claim 2, the training the middle tube as a metal tube with longitudinal slots. According to claim 3 are advantageous also the inner and the outer tube formed as metal tubes.

Advantageous are according to claim 4, the transverse slots one behind the other and formed offset in the circumferential direction. This results in with simple construction a good all-round bendability.

at An Abwinkelungsstelle can lead to mounting problems, if the inner tube should be inserted and too stiff to go through the Abwinkelungsstelle is. Therefore, the features are advantageous of claim 6 provided. When passing through the bend point Regions of the inner tube are formed bendable, can be the inner tube without problems in its final assembly position slide.

is the middle tube slotted longitudinally in a straight position and then it is in an angled outer tube introduced, so inevitably results in a bend the bendable areas. To avoid this are advantageous the Features of claim 7 is provided. In such a trained middle tube stand in spite of the Abwinkelungsstelle in the rigid section the bendable areas in their rest position straight.

In In the drawings, the invention is for example and schematically shown. Show it:

1 a schematic side view of a shaft according to the invention in the first embodiment,

2 a highly schematic enlarged section along line 2-2 in 1 transverse to the axis of the shaft,

3 a view according to 1 by a Embodiment of the first embodiment with different bending characteristics,

4 a highly schematic section across the axis of a shaft of a second embodiment,

5 an enlarged real representation of the section V from 4 .

6 a side view of the outer tube of the construction of 4 .

7 a side view of the middle tube of the construction of 4 .

8th a side view of the inner tube of the construction of 4 .

9 a side view of a shaft having a Abwinkelungsstelle in its rigid section,

10 the side view of a central tube in for the construction of 9 appropriate education and

11 a side view of a shaft having three Abwinkelungsstellen in its rigid section.

1 shows a first embodiment of a tubular shaft according to the invention 1 , The shaft is in 2 shown in section and shows in the highly schematic representations of 1 and 2 a pipe 2 in a rigid section 3 is rigid and in subsequent thereto at the ends of bendable areas 4 and 5 is formed bendable. To the bendable areas 4 and 5 In turn, additional areas can be applied at the ends, such as rigid end regions in the example shown 6 ,

As 2 shows, the shaft is 1 of four bars 7 . 8th . 9 . 10 run through. Of these are in 1 only two, namely the rods 7 and 9 shown in dashed lines. As 2 shows are the rods 7 - 10 in guides 11 stored on the pipe 2 are attached. The bars 7 - 10 are thus secured in the guides against lateral deflections, but can move longitudinally in the guides.

As 1 shows, the rods are lost 7 and 9 thus by the bends in the bendable areas 4 . 5 always parallel to the wall of the pipe 2 , At the ends are the rods 7 - 10 at tailpipes 12 attached in 1 also shown in dashed lines. These tailpipes 12 are axially parallel in the shaft 1 guided in the embodiment in the rigid end regions 6 ,

In 1 are from the four bars 7 - 10 For the sake of clarity, only the two rods 7 and 9 shown. The construction of the 1 and 2 can also z. B. have only three distributed over the circumference arranged rods, or more than four.

Because the rods 7 - 10 in the guides 11 secured against lateral deflection, and since they are at the ends of the tailpipes 12 are fixed and thus their ends always on a plane transverse to the axis of the shaft 1 are held, there is a forced movement, which will be explained below.

Is according to 1 the bendable area 4 in the direction of the arrow 13 bent, so shortens in this area 4 the pole 9 while the pole 7 must extend. Since the rods are longitudinally displaceable in the guides 11 are stored, the rods move accordingly in the rigid area 1 , At the other two rods 8th . 10 , in the case of bending according to 1 no shift.

Because the length of the rods 7 . 9 , between the tailpipes 12 is constant and one. lateral deflection is nowhere possible except at the second bendable area 5 , this one must be in 1 represented sense in the direction of the arrow 14 bend, in which case within the bendable range 5 the bars 9 extended and the rod 7 is shortened.

If the bending of the one bendable area 4 in another direction, z. B. perpendicular to the plane of the drawing, so the bendable area bends 5 in a corresponding manner perpendicular to the plane of the drawing.

3 shows a variant in illustration according to 1 , As far as possible, the same reference numbers are used. On average according to 2 agrees the construction of 3 with the 1 match.

Different in the construction of the 3 it's just that the rods 7 . 9 , in the rigid section 3 of the shaft 1 run crosswise. This is achieved in a simple way by the fact that they come in this area, ie in the derived section 3 the circumference of the pipe 2 Follow on a helix, by appropriate arrangement and training of the guides 11 is predetermined.

It turns out that when bending the bendable area 4 the construction of the 3 in the direction of the arrow 13 in the same sense as in the presentation of the 1 , the second bendable area 5 is again forcibly bent, but in the opposite sense as in the construction of the 1 ,

So it is possible, according to the design variants of 1 and 3 shafts 1 in such a way that when the one section is bent in one direction, the other section is forcibly bent in either one direction or the other.

In the construction of the 3 are the rods 7 . 9 , in the rigid section 3 circumferentially offset by 180 ° between the ends of this section. Would here the screw twisting of the rods 7 - 10 not over 180 °, but only over z. B. 90 °, as would result in the movement of the area 4 of the 3 in the manner shown a movement of the other bendable area 5 upwards out of the drawing plane.

The 4 - 8th show a fundamentally different second embodiment of the shaft 1 , again as far as possible the previous reference numerals are used. The shaft 1 is tubular from three tightly inserted tubes and that an outer tube 15 , a middle tube 16 and an inner tube 17 ,

4 shows the interlocking arrangement of these three tubes in section perpendicular to the tube axis. A section V of the section of the 4 is in 5 magnified and shown in real terms, however, to simplify the drawing without showing the curvature of the pipe. The pipes are in side view in the 6 - 8th shown.

The pipes 15 . 16 and 17 exist in the embodiment of metal and z. B. cut with laser in their special shape. 5 shows that the pipes 15 . 16 and 17 very close together, so are arranged as possible without a gap, so that the inner tube 17 and the outer tube 15 the middle tube 16 include tightly between themselves. As material for the pipes 15 . 16 and 17 is z. B. spring steel suitable.

The outer tube 15 and the inner tube 17 are very similar. You point when you're with 1 compares the rigid section 3 on, at the side of the bendable areas 4 and 5 connect, in turn, which the rigid end sections 6 connect.

In the exemplary embodiment, the bendable areas 4 and 5 with wide slots running across the tube axis 18 Mistake. These are also in 4 with dashed areas of the pipes 15 and 17 indicated. The slots 18 are like that 6 and 8th show in the axial direction one behind the other alternately arranged at 90 ° angularly offset and give a structure that is bendable in all directions, while always maintaining their circumferential length.

In alternative, but less simple training, could be used for the bendable areas and a joint construction, as in EP 1 681 013 A1 is described.

The middle tube 16 whose essential details are given in 7 as in 5 are shown, as these figures show, at the ends with closed end pipes 12 Mistake. In the intermediate area is the pipe 16 longitudinally slotted with longitudinal slots 19 with which the pipe in this area in bars 20 is divided, which at the very narrow longitudinal slots 19 close to each other, like 5 in the enlarged view shows. The rods are therefore based in the periphery laterally close to each other and can not avoid pressure and tensile load, so are as safe against lateral evasion as the rods 7 - 10 in the construction of 1 and 2 in the guides 11 ,

In the embodiment of the 4 - 8th the shaft reacts 1 in bending as well as in the embodiment of 1 , This requires the three tubes 15 . 16 and 17 be pushed over each other in a relative longitudinal position, as they are characterized by the superposition of the 6 - 8th in the drawing results. The middle tube 16 So lies with the tailpipes 12 in the rigid end areas 6 the inside and outside adjacent pipes 15 and 17 , The tailpipes 12 be through their leadership between the two pipes 15 and 17 held parallel to the tube axis. The bars 20 of the middle tube 16 can not escape laterally due to their close juxtaposition. Bends in this construction the one bendable area 4 so must the other bendable area 5 follow with a forced bend, as in the case of 1 was explained.

Also in the embodiment of the 4 - 8th can the variant of the 3 be realized. This requires the rods 20 of the middle tube 16 in the rigid area 3 that is, between the bendable areas 4 and 5 be helically wound trained.

The shaft according to the invention 1 can be used as a shaft of a surgical instrument. For example, it can form the shaft of an endoscope, wherein in the interior of the tubular shaft 1 the facilities of an endoscope are laid, such. As image guide, light guide, working channel, electrical cables, etc. At one end, a window may be provided through which a lens looks, while at the other end are arranged manual control devices. Likewise, the shaft according to the invention can also be used as a shaft z. B. one laparoscopic instrument, such as As a pair of pliers are used. Then at one end a handle and at the other end a forceps jaw is arranged.

For required rotational actuations over the length of the shank z. B. in the embodiment of 4 - 8th the pipes 15 and 17 be twisted against each other, which is also possible in the bent state. Relative longitudinal displacements are also possible.

The bars 7 - 10 respectively. 19 must be well slidably formed or arranged on all sides, so that there is a proper, precise forced bend in the inventive shaft. For this purpose, the rods, or their applying surfaces z. B. polished, lubricated, coated or otherwise designed to reduce friction.

The 9 - 11 show modified embodiments of the shaft according to the invention 1 in which, as far as possible, the same reference numerals as in the above-described figures are used.

9 shows a shaft 1 in fully assembled condition, so that all three tubes are plugged into each other. There are from the outside the individual sections of the shaft 1 to recognize and that the rigid section 3 and the bendable areas 4 . 5 as well as the rigid end areas 6 , In contrast to the previously described embodiments is in the construction of the 9 the rigid section 3 with a bend point 30 Mistake. The rigid section 3 is continuously rigid, even at the Abwinkelungsstelle 30 , The basic function of the shaft 1 is the same as previously described. Will the bendable area 4 bent sideways so forcibly bends the other bendable area 5 in the other direction.

In the middle position should the bendable areas 4 . 5 however, just like that 9 shows.

To achieve this is how 10 shows that in the construction of the 9 used slotted middle tube 16 in the in 10 made shown shape, including the Abwinkelungsstelle 30 and with straight bendable areas 4 and 5 , This training of the middle tube 16 ensures that, as in 9 shown in the straight position of the bendable area 4 also the bendable area 5 is just standing.

11 shows a variant too 9 at the the rigid section 3 with three bending points 30 is provided.

The shaft 1 in embodiment according to 11 would be useful as a shank pliers z. B. according to DE 20 2009 007 592 U . 1 is trained. It would only be at one end of the shaft 1 to attach the handle and at the other end the pliers mouth.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - EP 1708609 B1 [0002]
• US 7410483 B2 [0002]
• - US 7147650 B2 [0002]
• - EP 1681013 A1 [0041]
• - DE 202009007592 U [0053]

Claims (6)

Tubular shaft ( 1 ) of a surgical instrument with a rigid section ( 3 ), at each of whose ends a bendable region ( 4 . 5 ), wherein at least the rigid section ( 3 ) and the two bendable areas ( 4 . 5 ) of bendable, tension and pressure resistant rods ( 7 . 8th . 9 . 10 ; 20 ) are passed through, of which several over the circumference of the shaft ( 1 ) are arranged, wherein the rods ( 7 . 8th . 9 . 10 ; 20 ) longitudinally displaceable and fixed in the circumferential direction on the shaft ( 1 ) are mounted and at the ends in each case at a parallel to the axis of the shaft ( 1 ) guided tailpipe ( 12 ) are fastened, characterized in that the shaft ( 1 ) of three concentrically and closely slidably into each other slidable tubes ( 15 . 16 . 17 ), wherein the outer tube ( 15 ) in the rigid section ( 3 ) rigid and the inner tube ( 17 ) and the outer tube ( 15 ) in the bendable areas ( 4 . 5 ) are formed bendable without significant change in the circumferential length, and wherein the middle tube ( 16 ) at its ends the tailpipes ( 12 ) and in the area between these with narrow longitudinal slots ( 19 ) in slidably adjoining bars ( 20 ), the rigid section ( 3 ) of the shaft ( 1 ) at least one Abwinkelungsstelle ( 30 ) having. Shaft according to claim 1, characterized in that the middle tube ( 16 ) as a metal tube with longitudinal slots ( 19 ) is trained. Shaft according to one of claims 1 or 2, characterized in that the inner tube ( 17 ) and / or the outer tube ( 15 ) are formed as metal tubes, which at the bendable sections ( 4 . 5 ) with transverse slots ( 18 ) are provided. Shaft according to claim 3, characterized in that the transverse slots ( 18 ) are arranged one behind the other in the longitudinal direction and alternately offset in the circumferential direction. Shaft according to one of claims 1-4, characterized in that the inner tube ( 17 ) in the when inserted into the outer tube ( 15 ) through the Abwinkelungsstellen ( 30 ) is formed bendable areas to be pushed. Shaft according to one of claims 1-5, characterized in that the middle tube ( 16 ) angled preformed longitudinally slotted is formed.

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