CATHETER DEVICE COMPRISING A SEPARATING DEVICE FOR RETAINING MAGNETIC PARTICLES CONTAINED IN A FLUID AND PROTECTION DEVICE FOR A FUNCTIONAL ELEMENT

Abstract

The invention relates to, amongst other things, a catheter device comprising a catheter (24) in which a rotating shaft (25) which is made at least partially from a magnetic material is arranged, and a separating device which contains an annular body (27) surrounding the rotating shaft and having a cavity containing a magnetic body (13′), the magnetic body being arranged downstream from a point at which the shaft (25) exits the catheter (24) which it surrounds with respect to the direction of flow of the fluid through the catheter.

Claims

1. A catheter device with a catheter (24), in which a rotating shaft (25) consisting at least partly of a magnetic material is arranged, and with a separating device which comprises a ring body (27) with a cavity containing a magnet body (13′), the ring body surrounding the rotating shaft, wherein the magnet body with respect to the flow direction of the fluid through the catheter is arranged downstream of a location, at which the shaft (25) exits out of the catheter (24) surrounding it.

2. A catheter device for holding back magnetic particles (15, 16) which are located in a fluid, with a transport channel (1, 1′), in which the fluid can be moved in a throughflow direction (4, 5, 6), and with a magnet device (13, 13′, 13″, 14, 18, 19, 20), wherein the magnet device comprises at least one magnet (13, 13′, 13″) which is separated from the fluid by a magnetically permeable solid matter layer (14).

3. A catheter device according to claim 2, characterised in that the magnet interacts exclusively with magnetic or magnetisable particles in the fluid in the transport channel.

4. A catheter device according to one of the preceding claims, characterised by a first and a second fluid connection (11, 12), between which the separating device forms a fluid-tight fluid channel.

5. A catheter device according to one of the preceding claims, characterised in that a magnet (13, 13″) which is enveloped by a magnetically permeable solid matter layer (14) and around which fluid can flow is arranged in the fluid channel.

6. A catheter device according to claim 5, characterised in that the magnet (13, 13″) is designed as a cylinder or cuboid, whose length in the longitudinal direction of the fluid channel is larger than its diameter, and which is arranged in a cylindrical section of the fluid channel.

7. A catheter device according to claim 6, characterised in that the magnetic field lines within the magnet (13, 13″) run transversely, in particular perpendicularly to the flow direction of the fluid.

8. A catheter device according to claim 5, characterised in that the magnet (13, 13′, 13″) in the throughflow direction has a smaller extension than perpendicularly to the throughflow direction.

9. A catheter device according to one of the preceding claims, characterised by a ring body (27) which surrounds the transport channel (1′), wherein the transport channel is configured for receiving a catheter (24) with a throughflow channel, and wherein a magnet (13′) is arranged in the ring body (27) in a cavity situated next to the transport channel.

10. A catheter device according to claim 9, characterised in that the ring body (27) is designed as one piece in the peripheral direction.

11. A catheter device according to claim 9, characterised in that the ring body (27) is interrupted at least once in the peripheral direction and in particular can be folded open for sticking onto a catheter (24).

12. A catheter device according to claim 1 or one of the following, characterised in that the flow channel in the region of the magnet device (13, 13′, 13″, 14, 18, 19, 20) has a greater cross section than in a region which in the flow direction of the fluid is arranged upstream of the region of the magnet device.

13. A catheter device according to one of the claims 1 to 12, characterised in that this comprises at least one valve for the control of a fluid flow through the catheter, wherein the valve comprises: a valve control space, in which a feed channel runs out with a feed opening and a discharge channel runs out with a discharge opening, and a closure element which is movable in a controlled manner in the valve control space and which in at least one first position closes the discharge opening, in at least one second position closes the feed opening and in at least one third position holds open a connection channel between the feed opening and the discharge opening, wherein a valve drive is provided which moves the closure element selectively at least into the first, second or third position.

14. A catheter device according to one of the preceding claims, characterised in that the transport channel (1, 1′) comprises a reservoir for the intermediate storage of particles.

15. A catheter device according to claim 14, characterised in that the reservoir is magnetically influenced such that metallic particles remain in the reservoir even when the transport channel (1, 1′) is subjected to throughflow.

16. A catheter device according to one of the claim 14 or 15, characterised in that the reservoir comprises two ends, wherein both are connected in a fluid-conducting manner to the transport channel (1, 1′).

17. A catheter device according to one of the claims 14 to 16, characterised in that the reservoir is designed as a cross-sectional enlargement of the transport channel (1, 1′) which is spatially delimited.

18. A protective device for a functional element which is in connection with a flowing fluid, characterised in that a separating device for holding back particles located in the fluid and with at least one magnet element is provided along a flow channel for the fluid, in particular a catheter, in a manner distanced to the functional element and in particular separated from this.

19. A protective device according to claim 18, characterised in that the functional element is a seal and/or bearing, in particular a ball bearing or plain bearing.

Description

[0046] The invention is hereinafter represented and explained by way of embodiment examples in figures of a drawing.

[0047] Thereby are shown in:

[0048] FIG. 1 in a longitudinal section, a separating device with a transport channel which is designed as a fluid channel and in which fluid flows around a magnet,

[0049] FIG. 2 a catheter device with a rotating shaft and with a separating device, in a longitudinal section,

[0050] FIG. 3 a cross section of the device which is shown in FIG. 2,

[0051] FIG. 4 a magnet device, with which the magnet around which fluid flows is magnetised transversely to the longitudinal direction of the fluid channel,

[0052] FIG. 5 a magnet which is magnetised in its longitudinal direction and in the longitudinal direction of the fluid channel,

[0053] FIG. 6 a valve which is connected to a separating device,

[0054] FIG. 7 a further valve which is connected to a separating device,

[0055] FIG. 8 a drive unit for a functional element which can be driven by way of a shaft rotating in a catheter,

[0056] FIG. 9 a modification of a drive unit according to FIG. 8,

[0057] FIG. 10 and FIG. 11 in each case, further designs of drive devices for a shafts rotating in a catheter as well as

[0058] FIG. 12 a modification of a drive unit according to FIG. 9.

[0059] FIG. 1 in a longitudinal section shows a transport channel 1 which is designed directly as a fluid channel, and leads a fluid, for example in the form of a saline solution. The fluid at a feed opening 2 enters into the transport channel 1 and exits out of this at the discharge opening 3. The flow directions are indicated by arrows 4, 5, 6. A holder 7 for a magnet device is provided at the end of the transport channel 1 which is situated upstream, whereas a further holder 8 for a magnet device is provided at the end which is situated downstream. The holders 7, 8 can be designed as star holders with fluid through-openings 9, 10. The cross section of the through-openings 9, 10 should thereby be so large that the holders 7, 8 represent no significant flow resistance to the liquid.

[0060] The feed opening 2 just as the discharge opening 3 can be connected in each case to a catheter, which for example can be pushed onto a connection piece 11, 12.

[0061] A magnet device with a permanent magnet 13 which is surrounded on all sides by an encasing 14 protecting the magnet from the influence of the corrosive fluid is arranged in the inside of the transport channel. The encasing can for example be a designed as a plastic encasing, a coating or also be designed as a metallisation, which is to say a metallic coating of a noble metal.

[0062] The flow of the fluid through the transport channel 1 will not be a strictly laminar flow, but will have certain turbulence or eddies. In any case, the particles 15, 16 which as magnetic particles are present in the fluid circuit for example due to the wearing of magnetic parts are attracted to certain regions of the magnet. By way of additional eddy elements in the transport channel 1, one can also ensure that the flow of the fluid is eddied, so that the probability of particles transported in the fluid getting into the proximity of the magnet is increased. The term “magnetic particles” thereby is to be understood as all particles which are attracted by a magnet, in particular, but not only ferromagnetic particles.

[0063] If the particles once get into a capture region of the magnet, then they are firmly held there and are held back from the fluid flow. The spearing device which is shown in FIG. 1 can be used as a disposable separating device for example, and be disposed of after use. The separated metal particles 15, 16 can remain on the magnet 13 in this case. One can also envisage the magnet 13 being designed as an electromagnet or being magnetised by a magnetising device from outside the transport channel. In both these cases, the magnetisation of the magnet 13 can be temporarily lifted, in order to rinse the transport channel and the outer surface of the magnet 13, 14 and to remove the magnetic particles 15, 16. In this case for example, another catheter can be connected to the connection piece 12, and this leads the fluid used for rising together with the particles into a capture container.

[0064] The magnet 13″ as is shown in FIG. 4 in more detail, can be magnetised for example by way of an external magnetisation device 17 with an electromagnet part 18 as well as pole shoes 19, 20, so that its magnetisation direction runs along the arrows 21, 22 which are shown in FIG. 4, transversely to the longitudinal direction of the transport channel (assuming that the magnet represented in FIG. 4 is used for a device as is represented in FIG. 1). The electromagnet 18 can then be simply switched off for rinsing or its effect can be at least partly reversed, in order to overcome the residual magnetisation of the magnet 13.

[0065] A further constructional form of a magnet is represented in FIG. 5, wherein its outer geometric shape corresponds to that of the magnet represented in FIG. 1, wherein the magnetisation, indicated by the arrow 23, runs in the longitudinal direction of the magnet 13.

[0066] Metallic particles with the use of such a magnet would tend to collect rather at the two axial ends than on the longitudinal sides as with a magnet magnetised transversely to the longitudinal direction and represented in FIG. 4.

[0067] FIG. 2 shows a catheter device with a catheter 24, in which a rotating metallic shaft 25 is guided. A catheter holder which comprises a transport channel 1′ is indicated with the reference numeral 26 in FIG. 2. The reference numeral 27 indicates a housing which surrounds the catheter holder 26 and forms a ring body comprising a cavity, in which a magnet 13′ is arranged. The shaft 25 exits the catheter 24 within the housing 27. The catheter 24 exits from the catheter holder 26 or ends at one end of the catheter holder 26. In any case, the fluid which is located in the catheter 24 and which flows slowly along the shaft 25 as a rinsing and lubricating fluid can enter into a fluid channel 28 which is formed at the end of the catheter 24 and which has a significantly larger cross section than the free cross section of the catheter 24 which is already reduced by the shaft 25 which is led in this. The fluid channel 28 is located upstream of a mechanical bearing 29 which can be designed as a plain bearing, and in the direct region of influence of the magnet 13′. The magnet 13′ is designed as a permanent magnet but can however also be designed as an electromagnet.

[0068] The magnetic particles 30 in the region of the fluid channel 28 collect on the wall of the channel which faces the magnet 13′. The magnetic particles are held back from the fluid in this manner and do not get to the bearing 29.

[0069] The further course of the shaft 25 is not represented, but further mechanically functioning parts, such as for example pumps or millers which are driven by a shaft and which must be protected from the influence of the magnetic particles, can be provided distally of the connection coupling in the further course. The housing 27 apart from the catheter holder 26 yet accommodates a rinsing device with connection pieces 32, 33 for a rinsing fluid, in order to rinse the catheter 24.

[0070] The magnet 13′ can be withdrawn from the housing 27 so as to remove the captured magnetic particles 30, so that the magnetic particles can then be rinsed away. This should be effected outside the operating time of the shaft and the respective bearings and functional elements, in order to take care of these. If with regard to the magnet 13′ it is the case of an electromagnet, then this can be simply temporarily switched off for the rinsing.

[0071] A cross section through the catheter arrangement of FIG. 2 is shown in FIG. 3, with the housing 27, the transport channel 28 in the region behind the end of the catheter 24 as well as the magnet 13′ which is located in a cavity of the housing 27.

[0072] FIG. 6 shows a magnet valve with a transport channel 1″, through which a fluid flows between a feed opening 2′ and a discharge opening 3′. A closure body 50 can be driven within the transport channel 1″ between a first closure position and a second closure position, wherein a first closure surface 51 closes a valve opening 51a in the first closure position, whereas a closure surface 52 closes a valve opening 52a in the second closure position.

[0073] Two armature bodies 53, 54 are integrated into the closure body 50 and are drivable by the magnetic field of two valve drive coils 55, 56. The magnet 13″ of the separating device is arranged axially between the armature bodies 53, 54, in a manner aligned manner to these. The armature bodies with the magnet body 13″ are provided with a common solid matter encasing.

[0074] Holding springs 57, 58, in the absence of an excitation of the valve drive coils hold the closure body in a middle position, in which the valve is opened. Two plain bearings 59, 60 are provided at the ends of the valve housing for guiding the closure body 50.

[0075] FIG. 7 shows a valve with a feed opening 2″, with a discharge opening 3″ and with a closure body 50′. The closure body 50′ is can be driven within the transport channel 1″ between a first closure position and a second closure position, wherein a first closure surface 51′ closes a valve opening 51a′ in the first closure position, whereas a closure surface 52′ closes a valve opening 52a′ in the second closure position. The closure body 50′ is mounted in the housing of the valve by way of an elastic, permeable disc 61 and is held in an opened middle position. The disc 61 carries separating magnets 13′″, 13″″ which are connected in the closure body 50′ to valve drive armatures 62, 63 and together with these are encased by a protective layer.

[0076] The valve drive armatures 62, 63 are drivable in the field of the coils 64, 65. Particles in the transport channel can settle on the separating magnets on the protective layer and are firmly held there.

[0077] FIG. 8 shows a drive device with a drive armature 66 which can be driven in rotation and which drives a rotating shaft 67 in a catheter 68. A feed channel 69 is arranged radially to the outside, and a return channel 70 is arranged radially to the inside, in a manner concentrically to one another within the catheter 68, and arranged to the outer envelope of the catheter. The feed channel 69 and the return channel 70 are separated from one another by a hose-like separating wall 71.

[0078] A rinsing fluid is pumped from a reservoir 73 through a cannula 74 and a valve 75 by way of a volume-controlled peristaltic pump 72. Two magnets 76 and 77 serve for the drive of the valve and are activated by way of a pressure switch 78 with the aim of maintaining a constant pressure in the feed channel 69. The fluid for this is led through the valve 75 and through the housing of the drive armature 66, through the transport channel 9 and through the separating device 80 where particles are actively filtered out of the fluid. The separating device 80 can be constructed as with the separating device shown in FIG. 1. From there, the fluid flows into the catheter 68 radially outwards through the feed channel 69 and radially inwards through the return channel 70, as well as from there to a peristaltic pump 81 which sucks the fluid and leads into the reservoir 82. The peristaltic pump 81 however can also serve for back-rinsing and for this purpose can be operated in a manner such that it delivers the fluid to the return channel 70 and from there via the feed channel 69, through the separating device back to the valve 75 into the reservoir 73, in order for example to remove the captured particles from the separating device.

[0079] FIG. 9 shows a construction similar to that of FIG. 8, wherein additionally to the valve 75, a second valve 75′ is arranged between the return channel 70 and the return pump 80, in front of the drive armature 66 and behind the peristaltic pump 72. Whilst FIG. 8 is applied with rinsing systems, in which no undesired vacuum is produced in the return due to installation components, it is possible to apply FIG. 9 also with rinsing systems, in which an undesired vacuum arises in the return (e.g. due to the winding direction of the flexible shaft). This vacuum is recognised by the sensor which then, by way of closing the valve 75′ to the bottom, ensures that no medium gets out of the container 82 via the pump 81 into the rinsing circuit. The separating device is thus arranged between two valves and also between two fluid delivery devices, of which at least one, in particular both, can be switched over with respect to the delivery direction of the fluid, in order to reverse the flow direction.

[0080] With regard to the construction according to FIG. 10, in comparison to the construction in FIG. 8, only a peristaltic pump 72 is replaced by a reservoir 83 which permits a gravity flushing, by way of the fluid flowing through the valve 75 and further to the catheter 68 due to gravity. The rotating shaft 84 within the catheter 68, due to its stranded/twisted construction based on twisted strands has a helical (coiled) outer structure, which on rotation gives this itself a pumping effect in the direction away from the drive armature 66. Another variant with a volume-controlled peristaltic pump 72 and with a reservoir 73 is represented on the right side of FIG. 19, to the right of the dashed line 85, for the feed of fluid to the catheter 68. The peristaltic pump there delivers the fluid to the inside of the catheter which for example is introduced into the body of a patient and there ends at a heart pump 85 with a rotor 85a. The heart pump for example can be radially compressed which is to say as a whole can be particularly prone to particles which get therein. The fluid then flows back from there. A separating device 80 can be provided in each case upstream of the catheter 68 in the flow direction, between this and the delivery device 73, 83, in particular in any case upstream of the heart pump 85.

[0081] FIG. 11 shows a constellation similar to that of FIG. 9, wherein a gravity delivery 83 is envisaged instead of the peristaltic pump 72, wherein on normal operation, fluid leads from there via the valve into the catheter 68 and there firstly radially outwards through the feed channel 69, radially inwards into the return channel 70 as well as from there to a peristaltic pump 81 which sucks the fluid and leads into the reservoir 82. The fluid, between the return channel 70 and the peristaltic pump 81 firstly passes the separating device 80 which is arranged between the return channel and the housing of the drive armature 66. The fluid thereafter flows past the drive armature 66 to the peristaltic pump 81. The mounting of the drive armature can be relatively insensitive, so that the through-flow direction of the fluid there is of minor significance. What is important is that that the housing of the drive armature is supplied with fluid to ensure a good lubrication. The selected arrangement moreover ensures that magnetic wear particles of the rotating shaft 84 in this case cannot damage the bearings of the drive armature.

[0082] FIG. 12 shows a construction similar to FIG. 9, wherein a further separating device 80′ ensures that the function of the sealing surfaces of the valve 75′ is not compromised by clinging particles.

[0083] The invention, in particular with medical applications, but also with other applications, permits magnetic particles to be held back from a fluid flow with the help of magnet devices, wherein the magnets of the magnet devices are protected from the corrosive effects of the fluid.

[0084] The catheter device according to the invention can be combined with all separating devices which are represented here, thus for example separating devices according to one of the aspects 1 to 11 which are specified below and/or further separating device according to the description of the figures and the current patent claims. For this, it is also possible to not only provided one, but also several separating devices per catheter device.

[0085] With respect to the separating devices, in particular, the following aspects apply:

[0086] 1. A separating device for holding back magnetic particles which are located in a fluid, with a transport channel, in which the fluid can be moved in a throughflow direction, and with a magnet device, wherein the magnet device comprises at least one magnet which is separated from the fluid by a magnetically permeable solid matter layer.

[0087] 2. A separating device according to aspect 1, characterised in that the magnet exclusively interacts with magnetic or magnetisable particles in the fluid in the transport channel.

[0088] 3. A separating device according to aspect 1 or 2, characterised by [0089] a first and a second fluid connection, between which the separating device forms a fluid-tight fluid channel.

[0090] 4. A separating device according to aspect 1, 2 or 3, characterised in that [0091] a magnet which is enveloped by a magnetically permeable solid matter layer and around which fluid can flow on all sides, is arranged in the fluid channel.

[0092] 5. A separating device according to aspect 4, characterised in that [0093] the magnet is designed as a cylinder or cuboid, whose length in the longitudinal direction of the fluid channel is larger than its diameter, and which is arranged in a cylindrical section of the fluid channel.

[0094] 6. A separating device according to aspect 5, characterised in that [0095] the magnetic field lines run within the magnet, transversely, in particular perpendicularly to the flow direction of the fluid.

[0096] 7. A separating device according to aspect 4, characterised in that [0097] the magnet in the throughflow direction has a smaller extension than perpendicular to the throughflow direction.

[0098] 8. A separating device according to aspect 1, 2 or 3, characterised by [0099] a ring body which surrounds the transport channel, wherein the transport channel is configured to receive a catheter with a throughflow channel, and wherein a magnet is arranged in the ring body, in a cavity situated next to the transport channel.

[0100] 9. A separating device according to aspect 8, characterised in that [0101] the ring body is designed as one piece in the peripheral direction.

[0102] 10. A separating device according to aspect 8, characterised in that [0103] the ring body in the peripheral direction is interrupted at least once and in particular can be folded open for sticking onto a catheter.

[0104] 11. A separating device according to aspect 1 or one of the following, characterised in that [0105] the flow channel in the region of the magnet device has a larger cross section than in a region which in the flow direction of the fluid is arranged upstream of the region of the magnet device.

[0106] 12. A catheter device with a catheter, in which a rotating shaft consisting at least partly of a magnetic material is arranged, and with a separating device which comprises a ring body which surrounds the rotating shaft and is with a cavity containing a magnet body, wherein the magnet body with respect to the flow direction of the fluid through the catheter is arranged downstream of a location, at which the shaft exits out of the catheter surrounding it.

[0107] 13. A protective device for a functional element, which is in connection with a flowing fluid, characterised in that a separating device for holding back particles located in the fluid and with at least one magnet element, in particular a separating device according to one of the aspects 1 to 11, is provided along a flow channel for the fluid, in particular a catheter, in a manner distanced to the functional element and in particular separated from it.

[0108] 14. A catheter system comprising a separating device according to one of the aspects 1 to 11, and/or a protective device according to aspect 13, characterised in that at least one electrical element for the control of the functional element and/or for the magnet control can be separated from the remaining catheter system.