Hand-held actuator device

Abstract

A hand-held actuator device for releasing into the body from a delivery system a medical prosthesis, like a stent, comprising a frame that acts as a housing, a reel for receiving a wire, a manually operable slider mounted to the frame and a one-way connection between the slider and the reel. Actuating the slider causes the reel to wind up the wire and release the medical prosthesis.

Claims

1. A device for releasing into a body from a delivery system a medical prosthesis, comprising: a housing frame including a distal bearing hub; an inner housing tube communicating with the distal bearing hub, the inner housing tube extending through the housing frame to a proximal hub; a reel rotatably mounted to the housing frame adjacent the proximal hub, the reel designed to wind a wire extending into the housing frame through the distal bearing hub; a slider operably connected to the reel, the slider mounted to the housing frame; a connection comprising at least one reel disc that engages the slider and the reel during a backward stroke and that disengages the slider and the reel during a forward stroke; and a detent comprising a first end that engages the reel and a second end that engages the wire.

2. The device of claim 1, wherein the first end of the detent functions as a pawl by engaging the reel.

3. The device of claim 2, wherein the second end of the detent guides the wire toward the reel.

4. The device of claim 3, wherein the at least one reel disc includes a toothed circumferential surface.

5. The device of claim 1, further comprising a track mounted to the housing frame, wherein the slider is configured to slide along the track.

6. The device of claim 5, wherein the slider comprises a release element that is moveable between a relaxed gripping disposition and a pushed down release disposition.

7. The device of claim 1, wherein the at least one reel disc comprises a first reel disc and a second reel disc, and wherein the reel is flanked by the first reel disc and the second reel disc.

8. The device of claim 1, further comprising: a catheter having a proximal end extending through the distal bearing hub; a sheath disposed coaxially inside a distal end of the catheter and attached to the wire; and a self-expanding stent mounted in the sheath.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) FIG. 1 shows a longitudinal section of a preferred embodiment;

(2) FIG. 2 shows a transverse section along the line II-II in FIG. 1;

(3) FIG. 3 shows a transverse section along the line III-III in FIG. 1;

(4) FIG. 4 is a side view to show a borehole and a groove in the cylindrical drum of the reel;

(5) FIG. 5 is a front view of the drum of FIG. 4;

(6) FIG. 6 is a side view of an end of the wire; and

(7) FIG. 7 is a section along the line IV-IV in FIG. 3 seen from above.

DETAILED DESCRIPTION

(8) The invention can be embodied in a device for pulling a wire 8 out of a tube 14 and which can be activated, preferably with only one hand.

(9) The drawings show a preferred embodiment of the invention. FIG. 1 shows one half of a molded housing 10 which serves as a frame for mounting the various components of the device, and has a proximal end 20 and a distal end 22. The housing is almost symmetric and the two half housing parts are fixed together with screws 18 (or something similar like rivets or plugs) at defined places. A portion of each half of the housing is covered with a rubber material (not shown). This increases the grip and eases the handling of the device.

(10) A first hub 12 is fixed at the distal end 22 of the housing, acting as an abutment and bearing element for guiding the tube 14 to the housing 10. The tube 14 terminates in the hub 12, so that a wire 8 can be pulled out of the tube. The hub 12 acts as an abutment element and stops the tube 14 from being pulled into the housing 10. Through this abutment element extends an inner tube 26 to a second hub 24 at the proximal end 20 of the housing 10. The second hub 24 provides a female luer connector to engage a corresponding male luer, for flushing liquid for the lumen of the tube 14.

(11) A reel 30 is provided to take up the wire 8 and is preferably near the proximal end 20 of the housing 10 rotatably mounted in the housing. The reel is flanked by two large discs 30a, 30b, spaced apart by a cylindrical drum surface 30c of the reel for the wire. Both of the discs have a toothed circumferential surface to provide a ratchet element (see FIG. 3). In other embodiments there could be only one smooth wheel and one ratchet wheel instead of both wheels being ratchet wheels.

(12) The reel coils up the wire when it rotates in the direction of arrow A and would release the wire if it were able to rotate in the opposite direction.

(13) To attach the wire 8 to the reel 30 there is provided a special ball-end on the wire and 8 a borehole in the drum

(14) With reference to FIGS. 4, 5 and 6 a borehole 31 is provided in the cylindrical drum 30c. The borehole 31 leads from the surface of the cylindrical drum 30c, in a direction transverse to the rotatory axis into the drum 30c, to an abutment surface 31c. A groove 33 co-axial with the borehole 31 links the borehole with the surface of the drum.

(15) The end of the wire 8 carries a sleeve 9 and a ball Ba, welded to the end of the wire 8. The wire B is put with the free end into the sleeve 9 and the ball Sa stops the wire 8 from sliding through the sleeve 9. Another way fixing the 8 sleeve 9 to the wire 8 could be to weld the ball Sa on the wire 8 after putting it through the sleeve 9.

(16) In another embodiment the wire and the sleeve are pressed together such the sleeve 9 is fixed on the wire.

(17) The wire 8 is threaded into the groove 33 and the sleeve 9 is advanced into the borehole 31. Pulling the wire urges the sleeve to slide into the first borehole 31a, which has a diameter slightly bigger than the sleeve 9, and blocks the wire from being pulled further.

(18) To avoid releasing a coiled up wire, a backstroke-stopper 32 (otherwise called ‘detent’) is provided near the reel 30. In the preferred embodiment the stopper has two fingers. The first is a detent 32a which functions as a pawl by engaging the teeth of the ratchets 30a and/or 30b. The teeth of the ratchets are so shaped that the finger 32a does not prevent the ratchet from rotating in direction A, but stops the reel rotating in the other direction by engaging into a gap between adjacent teeth.

(19) The second finger 32b serves to press the already coiled wire towards the rotational axis of the reel. The wire is springy so it tends to straighten when it can and so will tend to unroll from the reel. The second finger prevents this happening. Preferably the second finger 32b has a recess 32ba (as shown in FIG. 2) facing the wire to receive the wire 8. When the second finger 32b presses down the wire 8, there is friction between the wire and the finger. This friction, together with the resilience of the wire, can act as a brake in the rotation of the reel. Indeed, such a brake can render any ratchet and pawl superfluous. One advantage of a brake over a ratchet in that one can achieve a stepless pulling of the wire 8.

(20) To urge the reel to rotate to wind in the wire 8, in direction A, a slider 34 is provided. This slider has a thumb pad 35 and is operably connected to the reel by its elongate extension 36 that has a toothed straight ratchet profile 38 at its end remote from the thumb pad. The toothed straight profile 38 and the toothed ratchet on the periphery of each of the reel discs 30a, 30b provide a one-way-connection 40 in which the reel rotates when the slider is moved in the direction of arrow B. When the discs are so urged to rotate, the drum 30c between the two discs is also rotating and the wire is coiled up. When the slider is urged in the reverse direction, arrow C, the teeth of the straight ratchet slide over the teeth of the discs (see 40). In another embodiment the straight ratchet and the discs may be fixedly connected such that both move together, in both directions. A one-way bearing in the hub of the reel allows the wire take-up reel to rotate in the direction of arrow A, but not in direction of arrow B. Of course the movement directions of the particular elements are changeable at will. For example, if the wire coils up anti-clockwise on the reel, rather than clockwise, each would be arranged the other way.

(21) The slider slides on a track 42, defined by the housing 10. The slider includes a slider release element 44, that is moveable between a relaxed gripping disposition and a pushed down release disposition. The release element, when not pushed down, is formed such that a detent 44a of the slider release element is blocked by a recess 46 the housing (as shown in FIG. 7). This restrains inadvertent sliding of the slider. When the slider is to be moved, the slider release element is first pushed down until the detent engages the corresponding locker element 34aa on the inner part of the slider 34a and is being held down. As a result the slider 34 is released from the recess 46 in the housing and is free to move along the track 42.

(22) In another embodiment there could be provided a distance scale (not shown) next to the sliding track advancing the distance indication by the slider.

(23) In another embodiment, there is provided a spring (not shown) in the housing 10, which is connected to the slider and urges the slider to slide back into the first pull back position automatically.

(24) As soon as the slider release element 44 is no longer pushed down, it moves up again as a result of its resilience and the ramps 44a and 34aa, once again to restrain slider movement.

(25) In the present embodiment all device members (reel, housing, slider, head, hub and stopper) are molded from plastics. In other embodiments components can be provided as separate individual parts (e.g. the reel in one smooth, smaller wheel and two ratchets). These parts can be formed of various materials (e.g. metal, different kinds of plastics) and assembled (by screwing, plugging, welding, riveting) as desired.