WO2020109695A1

WO2020109695A1 - Medical endoscope piston

Info

Publication number: WO2020109695A1
Application number: PCT/FR2019/052729
Authority: WO
Inventors: Hervé COLLIN
Original assignee: Advance Medical Integration Systems
Priority date: 2018-11-30
Filing date: 2019-11-15
Publication date: 2020-06-04
Also published as: FR3089109A1; FR3089109B1

Abstract

The invention relates to a sterilisable medical endoscope piston formed by a central rod (40) with a central channel, at least partially hollowed, which opens at one of the front surfaces and the head of which defines a seat for connecting to a fluid conduit, said head (41) and channel (40) being joined by an elastic means, characterised in that said assembly consists of one single part made of a flexible, elastic polymer.

Description

Title: MEDICAL ENDOSCOPIC PISTON

Field of the invention

The present invention relates to pistons for endoscopes, medical instruments which are used to explore the cavities of internal organs.

More specifically, the invention relates to pistons, generally for single use, controlling the flow of air or water. The suction and blowing / washing pistons are parts comprising several parts of different types, in particular a cylindrical piston, a body for mounting on the handle of an endoscope and a spring interposed between the body and the piston to ensure the shutter or opening function of the lights provided in the body of the handle, as well as the restoring force allowing the user to exert pressure in an ergonomic and controlled manner.

State of the art

Known in the prior art American patent US9408523B2 describing a single-use air / water flow valve which may include a main rod providing an air passage through the central bore of the main rod . The main stem is molded and placed in a mold to overmold seals on the main stem. Before the following steps, the retaining ring, the button cap and the protective bellows can be molded. The rear end of the main rod is placed through the center of the retaining ring and an elastic member (for example, a spring). The button cap is then placed on the main rod and attached to the latter.

US patent US9585545B2 relates to a disposable suction piston. The disposable suction piston includes a rod that provides air passage through the rod, a spring, a spring-loaded support spoon and a protective bellows. The process for manufacturing a single-use suction piston includes several steps. A rod and a spring support spoon are molded and a lower end of the rod is placed through the center of a spring. The lower end of the rod is placed through a rod opening in the spring support spoon and the tabs or spring support spoon are placed in the recessed openings in the rod. The protective bellows can be molded on the spring support spoon or molded and placed on the spring support spoon.

The patent application US2012031515 describes n a shut-off valve a fluid pipe connection. The shut-off valve includes a housing and a one-piece shut-off valve arranged inside the housing. The integral shutoff valve includes a spring region which defines a lumen and a sealing characteristic on one or both ends. The spring region defines one or more fluid passageways between an outer surface and an inner surface of the integral shut-off valve. The spring region can be in the form of a helical coil or a windowed tube. The sealing characteristic relates to a leaktight seal disposed between the housing and the shut-off valve formed in one piece.

This document in no way relates to a piston for endoscope, or even a piston in general, but a fluid connector intended for the connection of two coaxial segments of tubular conduits. Furthermore, the valve described in this document does not consist of a single monolithic part, but of an assembly of components, as is evident from the description and Figures 3 to 5.

Patent application WO2012175412 describes a valve which comprises a housing defining a flow path between a first end and a second end of the housing. The valve further comprises a piston device having a removable part, which is removable from a closed position, in which the flow of liquid in the flow path is prevented, to an open position, in which the flow of liquid in the flow path is allowed. The removable portion has a sealing portion configured to press against an interior sealing surface of the housing in the closed position of the piston device. The piston device includes furthermore a spring part configured to deflect the removable part towards the closed position. The spring part is an integral part of the piston device.

Patent application US2015144215 describes another example of an air / water valve assembly intended for use in an endoscope or other medical equipment is provided. The valve includes a slide valve and a one-piece seal including several seal rings. The coil can be injection molded and the sealing member can be molded onto the coil. A spring, a retainer and a housing are also included to form the valve assembly. As such, an air / water valve assembly can be manufactured for use in a single medical procedure and then discarded cost-effectively.

Disadvantages of the prior art

The solutions of the prior art consist of an assembly of metal parts (the spring) and plastic parts (the body, the rod and the support base). The assembly of such parts requires essentially manual interventions which can be compatible with the preparation of sterile parts. They also have connection zones which are difficult to sterilize. Sterilization is generally carried out using an EtO (ethylene oxide) sterilizer for a sufficient time so that the gas can penetrate all the interstices.

Solution provided by the invention

The present invention aims to avoid the drawbacks of the prior art by proposing a plunger for an endoscope, preferably for single use and disposable, easy to produce, with a reduced manufacturing cost and giving the user ergonomic, sterilizable handling. at EtO.

The invention relates, in its most general sense, to a sterilizable medical endoscopic piston according to claim 1.

According to variants,

- said central rod is flared at its proximal front end to form a disc-shaped head whose periphery is connected to a tubular ring forming the seat of the piston, coaxial with said central rod by an elastically deformable zone

- said elastically deformable zone is constituted by a mesh crown

- said elastically deformable zone is constituted by a crown of

helical arms.

- said elastically deformable zone is constituted by a crown of

interlocking helical arms

deformable radial arms extend between said central rod and said tubular ring

- Said central rod has an alternation of annular protuberances and annular grooves

- the piston is configured to cooperate with the suction valve body

of a handle of an endoscope or to cooperate with the air / water valve body of a handle of an endoscope.

The invention also relates to a disposable assembly formed by a suction piston and an air / water piston for an endoscope, characterized in that each of the pistons is constituted by a monolithic piece of flexible polymer and having a central rod having a channel. central at least partially recessed opening at one of the front surfaces and by a head defining a seat for the connection with a fluid conduit, said head and the channel being connected by elastic means.

The invention also relates to a method for manufacturing a single-use piston for an endoscope, comprising injecting an elastomeric plastic material into a mold for molding a monolithic part having a central rod having an at least partially hollowed out central channel leading to one of the front surfaces and by a head defining a seat for the connection with a fluid conduit, said head and the channel being linked by elastic means.

The invention also relates to a method of manufacturing a single-use piston by continuous liquid interphase printing of a monolithic part having a central rod having an at least partially hollowed out central channel opening to one of the front surfaces and by a head defining a seat for connection with a fluid conduit, said head and the channel being connected by elastic means. Detailed description of a nonlimiting example of embodiment

The invention is described below, by way of nonlimiting example, with reference to the appended drawings in which:

Figure 1 is an exploded partial perspective view showing an endoscope handle with the piston pair object of the invention

Figure 2 is a front view of a suction piston

Figure 3 shows a bottom view of said suction piston

Figure 4 is a front view of a suction blowing piston

Figure 5 shows a three-quarter view in front of said suction blowing piston

Context of the invention

Figure 1 shows an example of a known endoscope. It comprises a handle (1) from which extends a flexible tube (2) ending in a distal or operational end (3) which is introduced into the cavity to be explored and the orientation of which can be controlled by a sleeve stand (4). This sleeve is controlled by wires which are pulled in a controlled manner following the manual actuation of knobs or buttons (5, 6, 7) provided on the endoscope handle (1). The joystick control section allows the doctor to control all of the endoscope's functions. The lever handles (5, 6, 7) (space orientation) direct the lever cables and control the lever section at the distal end of the insertion tube, thereby enabling two-dimensional orientation. Locking mechanisms (brakes) make it possible to fix the leg section in the desired position.

Light is transmitted by an optical fiber (8), the proximal end (9) of which is coupled to an optical connector. The connection block (1 1) further comprises an air intake (10).

A pneumatic connector (12) is intended to be connected to a vacuum pump or a reversible air pump for controlling the insufflation or aspiration at the distal end (3). The technical unit (1 1) also includes an electrical connector (13) and a connection support (14) of a safety cord and a water supply (15). The handle (1) is connected to the tube (2) by a sheath (16) extended by a sleeve (17). The handle has an opening in the operating channel (18) fitted with a disposable biopsy piston valve (19).

The handle comprises a piston (20) controlling the washing channel and a piston (30) for controlling suction or insufflation by means of two tubes extending between the handle (1) and the distal end. (3), one to bring air and water to said distal end, the other to perform a biopsy or aspiration. The application of suction is regulated by means of a piston (30) provided on the handle. The piston is joined to a neighboring duct by welded connections. The pistons (20, 30) are coupled to the body of the handle by annular bases (32). The piston (30) connects the suction channel to the working channel in the insertion tube. By pressing the button (31) of the piston, one can perform a suction of the working channel. The air / water piston (20) is similar to the piston and the suction piston (30), except that a piston with a two-way button is used in a double channel device which allows air or water to the lens at the distal end, for washing or blowing air to improve vision. The two pistons (20, 30) can be detached for replacement, when they are for single use, or otherwise for cleaning.

Detailed description of the pistons (20, 30)

According to one aspect of the invention, a piston body for an endoscope is made of molded synthetic plastic and it has a straight bore passing through it, said bore having a lateral orifice, a first end of said bore being open to receive a mounted piston element. sliding in the bore to control communication between the second end of the bore and the side port, and the piston body having spaced apart formations on each side of the side port to properly position the piston body relative to the endoscope housing, whereby when the piston body is mounted in the housing, the piston body passes completely through it.

Since the bore is straight and the piston body is arranged to pass completely through the housing, the piston can very easily be cleaned by removing the piston element and having access to the bore from said first end. The piston element is preferably held in position in the bore by means of a sleeve which is screwed into said first end of the bore and which can be unscrewed to remove the piston element for cleaning the bore. A return spring can be arranged between the piston element and the sleeve to push the piston element back to its closed position in which there is no communication between the second end of the bore and the lateral orifice. . To open the piston, the piston element is moved against the force of the spring thus putting the second end of the bore in communication with the lateral orifice, this action simultaneously blocking the end of a central passage in the piston element through which the suction opens when the piston is in the closed position.

The piston body is conveniently molded from polypropylene and said formations are conveniently external ribs provided on the piston body, these ribs coming to bear against the housing at the level where the piston body emerges from said housing. One of said ribs can be elliptical to place the piston body -3- against a curved region of the endoscope housing. The other rib is preferably annular and it is arranged so as to position and retain the piston body against the housing using a clip clamp, allowing a certain degree of tolerance or play. Another aspect of the invention, an endoscope comprises a piston adapted to control the application of suction to the distal end of an endoscope rod, the piston being mounted in an endoscope handle housing and comprising a molded synthetic plastic piston body, said piston body having a straight bore therethrough, said bore having a lateral orifice communicating with a passage in the rod for applying suction to the distal end of said rod, an element of piston being slidably mounted in the bore between an open position for which the suction applied to the bore is transmitted to the lateral orifice, and a closed position in which the lateral orifice is not in communication with ec the second end of the bore, the piston body passing completely through the housing, so that at the first end of the body, the piston element, or a part attached to it, is accessible for manual actuation of the piston element and, at the other end of the piston body, the piston body is accessible from the outside of the housing to connect it to a suction source. Suction piston

Figures 2 and 3 show an example of a suction piston. It consists of a single piece without assembly, having a rod (40) through which a median channel opens out at the lower end. The other end of the rod (40) is flared to form a disc-shaped head (41). A mesh crown (42) formed by an intersection of arms (43) forms a frustoconical sleeve coaxial with the rod (40) extended by an annular ring (44). This mail crown (42) defines an axially compressible spring.

The annular ring (44) engages on the body of the handle suction valve to ensure a tight connection. Optionally, this annular ring (44) may have an internal thread.

Furthermore, radial arms (45) connect the annular ring (44) to the rod (40) to ensure centering while preserving an axial movement of the head (41) relative to the annular ring (40). The rod also comprises, in a known manner, an air passage through the central bore.

Air / water piston (30)

Figures 4 and 5 show an example of an air / water piston. It consists of a single piece without assembly, having a rod (40) through which a median channel opens out at the lower end. The other end of the rod (40) is flared to form a disc-shaped head (41). A deformable crown (42) formed by an assembly of arms (43) forms a frustoconical sleeve coaxial with the rod (40) extended by an annular ring (44). This annular ring (44) engages on the body of the suction valve of the handle to ensure a tight connection. Optionally, this annular ring (44) may have an internal thread.

The deformable crown (42) consists of a group of helical arms (48, 49) allowing elastic compression with a rotating movement.

The rod (40) has in known manner a seal (46) of conical shape and a radial lumen (47). Manufacturing process

The manufacture of the piston can be carried out by molding in a drawer mold.

It can also be achieved by additive manufacturing "from bottom to top", according to which a support is moved vertically in a back and forth movement relative to a building surface, in order to improve or accelerate the filling of the construction area with a solidifiable liquid. In preferred embodiments, the three-dimensional object is produced from a liquid interface by production of a continuous liquid interface (CLIP technology).

Another solution consists in implementing a method of forming the piston according to the invention consisting in using a support and an optically transparent element having a construction surface, the support and the construction surface delimiting a construction region between them. The construction region is filled with a polymerizable liquid; and exposing the building region to rays through the optically transparent member to form a solid polymer from the polymerizable liquid while simultaneously moving the support away from the building surface to form the three-dimensional object from the polymer solid, while simultaneously carrying out the following stages which consist in:

(i) continuously maintain a dead zone of polymerizable liquid in contact

with the building surface, and

(ii) (ii) continuously maintaining a polymerization zone gradient between the dead zone and the solid polymer and in contact with each of them, the polymerization zone gradient comprising a polymerizable liquid in a partially hardened form.

The pistons according to the invention can be combined in a sterile bag, to form a single-use piston kit.

Claims

1 - Piston for ensuring the shutter or opening function of the lights provided in the body of the medical handle of an endoscope, formed by a central rod (40) having an at least partially hollowed out central channel leading to one front surfaces and by a head defining a seat for the connection with a fluid conduit, said head (41) and the channel (40) being linked by an elastic means characterized in that said assembly is constituted by a single monolithic piece in a flexible and elastic polymer.

2 - Piston to ensure the shutter or opening function of the lights provided in the body of the medical handle of an endoscope, according to claim 1 characterized in that said central rod (40) is flared at its proximal front end to form a disc-shaped head, the periphery of which is connected to a tubular ring forming the seat of the piston, coaxial with said central rod by an elastically deformable zone.

3 - Piston to provide the shutter or opening function of the lights provided in the body of the medical handle of an endoscope, according to the preceding claim characterized in that said elastically deformable zone is constituted by a mesh crown (42) .

4 - Piston to ensure the shutter or opening function of the lights provided in the body of the medical handle of an endoscope, according to claim 2 characterized in that said elastically deformable zone (42) is constituted by a crown of helical arms (48, 49).

5 - Piston to ensure the shutter or opening function of the lights provided in the body of the medical handle of an endoscope, according to claim 2 characterized in that said elastically deformable zone is constituted by a crown of interlocking helical arms .

6 - Piston to ensure the shutter or opening function of the lights provided in the body of the medical handle of an endoscope, according to claim 2 characterized in that it comprises deformable radial arms extending between said central rod and said tubular ring.

7 - Piston to ensure the function of closing or opening the lights provided in the body of the medical handle of an endoscope, according to claim 1 characterized in that said central rod has an alternation of annular protuberance and annular grooves .

8 - Piston to ensure the shutter or opening function of the lights provided in the body of the medical handle of an endoscope, according to claim 1 characterized in that it is configured to cooperate with the valve body d aspiration of a handle from an endoscope.

9 - Piston to provide the shutter or opening function of the lights provided in the body of the medical handle of an endoscope, according to claim 1 characterized in that it is configured to cooperate with the air valve body / water from a handle of an endoscope.

10 - Single-use assembly formed by a suction piston and an air / water piston for endoscope characterized in that each of the pistons is constituted by a single monolithic part made of a flexible and elastic polymer formed by a central rod (40) having an at least partially hollowed-out central channel opening out to one of the front surfaces and through a head defining a seat for connection with a fluid conduit, said head (41) and the channel (40) being connected by elastic means.

1 1 - Method for manufacturing a single-use piston for endoscope according to claim 1, comprising injecting an elastomeric plastic material into a mold for molding a monolithic part having a central rod having an at least partially central channel recessed opening at one of the front surfaces and by a head defining a seat for the connection with a fluid conduit, said head and the channel being connected by elastic means. 12 - A method of manufacturing a disposable piston according to claim 1, by continuous liquid interphase printing of a monolithic part having a central rod having an at least partially hollowed out central channel opening to one of the front surfaces and by a head defining a seat for connection with a fluid conduit, said head and the channel being connected by elastic means.