SHELL FOR A PORTABLE ELECTROMECHANICAL APPARATUS FOR DRUG INFUSION

Abstract

Shell (11) for a portable electromechanical apparatus for drug infusion, comprising an outer casing (13) and a support structure (15) housed within the casing (13), wherein said casing (13) has a monolithic ring shape and is entirely made of plastics, and wherein said support structure (15) is at least partially made of metal.

Claims

1: A shell (11) for a portable electromechanical apparatus for drug infusion, comprising an outer casing (13) and a support structure (15) housed within the casing (13), wherein said casing (13) has a monolithic ring shape and is entirely made of plastics, and wherein said support structure (15) is at least partially made of metal.

2: The shell according to claim 1, wherein said casing (13) defines a shape substantially rectangular in plan and defines therein a chamber (17) having a corresponding shape in which said support structure (15) is housed, and wherein the flanks of the casing (13) have substantially the same width (“d”) over the entire perimeter so as to obtain high stiffness and strength of the monolithic structure of sad casing (13).

3: The shell according to claim 2, wherein said casing (13) surrounds at least four flanks of said chamber (17), and wherein at least one of the opposite bases (19,21) of said casing (13) is open.

4: The shell according to claim 1, wherein said casing (13) comprises a coupling ferrule (23) for firmly connecting a syringe (SR) to the shell of the apparatus, said ferrule (23) defining a bayonet-like coupling for said syringe (SR) and being incorporated in the body of said casing (13).

5: The shell according to claim 1, wherein said shell comprises a guide member (27) incorporated in the body of said casing (13) for a rod (29) which is longitudinally slidable and capable of exerting an axial thrust onto the plunger (SF) of a syringe (SR) associated with the shell (11).

6: The shell according to claim 1, wherein said support structure (15) comprises a base plate (31) and a frame (33) fixed to the plate (31).

7: The shell according to claim 6, wherein a seat (37) adapted to house the mechanical parts of an electromechanical driving unit is defined between the base plate (31) and the frame (33).

8: The shell according to claim 6 or 7, wherein the base plate (31) is substantially flat and rests against a plurality of rest elements (41) incorporated in the casing (13) and extending longitudinally and transversely within the chamber (17) of the casing (13) of the shell (11).

9: The shell according to claim 1, wherein said support structure (15) is firmly but detachably associated within the casing (13) in a distal position relative to said guide member (27).

10: The shell according to claim 5, wherein said sliding rod (29) and said guide member (27) have a non-circular cross-section, whereby rotation of the rod (29) relative to the guide member (27) is prevented.

11: The shell according to claim 2, wherein said casing (13) comprises a coupling ferrule (23) for firmly connecting a syringe (SR) to the shell of the apparatus, said ferrule (23) defining a bayonet-like coupling for said syringe (SR) and being incorporated in the body of said casing (13).

12: The shell according to claim 3, wherein said casing (13) comprises a coupling ferrule (23) for firmly connecting a syringe (SR) to the shell of the apparatus, said ferrule (23) defining a bayonet-like coupling for said syringe (SR) and being incorporated in the body of said casing (13).

13: The shell according to claim 2, wherein said shell comprises a guide member (27) incorporated in the body of said casing (13) for a rod (29) which is longitudinally slidable and capable of exerting an axial thrust onto the plunger (SF) of a syringe (SR) associated with the shell (11).

14: The shell according to claim 3, wherein said shell comprises a guide member (27) incorporated in the body of said casing (13) for a rod (29) which is longitudinally slidable and capable of exerting an axial thrust onto the plunger (SF) of a syringe (SR) associated with the shell (11).

15: The shell according to claim 4, wherein said shell comprises a guide member (27) incorporated in the body of said casing (13) for a rod (29) which is longitudinally slidable and capable of exerting an axial thrust onto the plunger (SF) of a syringe (SR) associated with the shell (11).

16: The shell according to claim 2, wherein said support structure (15) comprises a base plate (31) and a frame (33) fixed to the plate (31).

17: The shell according to claim 3, wherein said support structure (15) comprises a base plate (31) and a frame (33) fixed to the plate (31).

18: The shell according to claim 7, wherein the base plate (31) is substantially flat and rests against a plurality of rest elements (41) incorporated in the casing (13) and extending longitudinally and transversely within the chamber (17) of the casing (13) of the shell (11).

19: The shell according to claim 5, wherein said support structure (15) is firmly but detachably associated within the casing (13) in a distal position relative to said guide member (27).

20: The shell according to claim 6, wherein said sliding rod (29) and said guide member (27) have a non-circular cross-section, whereby rotation of the rod (29) relative to the guide member (27) is prevented.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Some preferred embodiments of the invention will be described below by way of non-limiting example with reference to the annexed drawings, in which:

[0037] FIG. 1 is a perspective view of a portable electromechanical apparatus for drug infusion that incorporates a shell according to a preferred embodiment of the invention;

[0038] FIG. 2 is a view similar to FIG. 1, in which the front panel of the apparatus has been removed;

[0039] FIG. 3 is a section taken along a longitudinal plane of the apparatus of FIG. 1;

[0040] FIG. 4 is a perspective view of the apparatus of FIG. 1 provided with a protective bell in its open condition;

[0041] FIG. 5 is a plan view of the apparatus of FIG. 1 provided with a protective bell in its open condition;

[0042] FIG. 6 è is a plan view of the apparatus of FIG. 1 provided with a protective bell in its closed condition.

[0043] In all the figures, the same reference numerals have been used to indicate same or functionally equivalent elements.

DESCRIPTION OF SOME PREFERRED EMBODIMENTS

[0044] Referring to the annexed figures, the shell for a portable electromechanical apparatus for drug infusion has been indicated as a whole with reference numeral 11.

[0045] According to the invention, the shell 11 mainly comprises an outer casing 13 and a support structure 15 housed within the casing 13. Advantageously, according to the invention, the casing 13 has a monolithic ring shape and is entirely made of plastics, preferably by means of the injection molding technique. In addition, still according to the invention, said support structure 15 is at least partially made of metal, preferably aluminum.

[0046] According to the invention, the ring-shaped structure of the monolithic casing 13 is substantially rectangular or square in plan, possibly with one or more rounded flanks that are convex towards the outside of the casing, and the flanks of the casing 13 have substantially the same width “d” over the entire perimeter, so as to obtain high stiffness and strength of the structure.

[0047] According to the shown embodiment of the invention, said casing 13 defines a shape substantially rectangular in plan with a convex flank 13a and defines therein a chamber 17 of corresponding shape in which said support structure 15 is housed. In other embodiments, the casing 13 may define annular shapes of any kind, for example circular or oval shapes, or shapes with square or hexagonal plan. In addition, the width “d” of said casing 13 is constant over the entire perimeter. Preferably, the convex flank 13a corresponds to the flank of the casing 13 on which the stresses generated during drug infusion are discharged.

[0048] As can be appreciated in the annexed figures, the casing 13 surrounds at least four flanks of said chamber 17 and comprises both opposite, open major bases 19,21. Said open bases 19,21 can, however, be closed by a corresponding lid that can advantageously be removed in order to get access to the chamber 17 enclosed in the casing 13.

[0049] Advantageously, the lid closing the open base 19 comprises a front panel 20 in which a display 22 and a set of control and programming keys 24 for controlling the apparatus are incorporated.

[0050] The casing 13 comprises, in the illustrated embodiment, a coupling ferrule 23 for firmly connecting a syringe SR to the shell 11 of the apparatus. The ferrule 23 defines a corresponding bayonet-like coupling for said syringe SR. In addition, the ferrule 23 is incorporated in the body of said casing 13, i.e. it is obtained as a single piece with the body of the casing 13 during the molding process for plastic materials.

[0051] Said ferrule 23 defines a bayonet-like coupling for a syringe SR provided with wings SA and comprises a pair of opposite arched seats 25a and a pair of diametrically opposite slits 25b, whereby the syringe SR can be engaged into the shell 11 by a coupling movement substantially comprising an axial approaching movement and a subsequent rotation about the axis of the syringe SR. In other embodiments, the ferrule 23 may define other types of coupling for the base of a syringe SR, for example of a syringe having a screw or complementary coupling provided inside or outside the body of the syringe SR.

[0052] The shell 11 according to the illustrated embodiment of the invention comprises a guide member 27 incorporated in the body of said casing 13. Said guide member 27 is advantageously capable of guiding the longitudinal sliding of a longitudinally slidable rod 29 and of exerting an axial thrust onto the plunger SF of a syringe SR associated with the shell 11 of the apparatus through the aforementioned ferrule 23.

[0053] Advantageously, according to the invention, the support structure 15 is preferably entirely made of metal, for example aluminum, in order to confer stiffness and strength, and it comprises a base plate 31 and a frame 33 fixed to the plate 31 by means of screws. Between the base plate 31 and the frame 33 there is defined a seat 37 capable of housing the mechanical parts of an electromechanical drive unit, arranged to cause exit of a drug from a syringe SR removably engaged in the shell 11. In addition, the base plate 31 is preferably substantially flat and, when housed in the chamber 17 defined within the casing 13 of the shell 11, rests against a plurality of rest elements 41 incorporated in the casing 13 and extending longitudinally and transversely within the chamber 17 of the casing 13 of the shell 11. The support structure 15 is firmly but detachably associated within the casing 13 of the shell 11, preferably in a position distal to said guide member 27.

[0054] An electric geared motor 43 and the contacts for a battery (not shown) powering said electric geared motor 43 can also be fixed to the frame 33. The battery may also be accessible through a door 47 provided on the adjacent flank of the casing 13 of the shell 11.

[0055] Advantageously, according to a preferred embodiment of the invention, the support structure 15 is housed in the chamber 17 defined by the casing 13, so that the stress exerted by the screw 53 during infusion is discharged against said rest elements 41. Advantageously, the ring-shaped structure of the monolithic casing 13 made of molded plastics and surrounding the chamber 17 brings about the necessary stiffness and strength for bearing the thrust exerted against said rest elements 41.

[0056] The longitudinally slidable rod 29 and the guide member 27 both have a non-circular cross-section, whereby rotation of the rod relative to the guide member is prevented.

[0057] In the illustrated embodiment, the cross-section of the rod and the cross-section of the guide member are complementary to each other and a minimum clearance is defined between the slidable rod 29 and the guide member 27, such as to allow axial sliding of the rod 29 without jamming, but also to prevent oscillations of the rod 29 relative to the guide member 27.

[0058] Still referring to the illustrated embodiment, the cross-section of the rod 29 and of the guide member 27 is oval or elliptical.

[0059] Still referring to the shown embodiment, the rod 29 comprises an axial cavity 49 having at least one open base 51 and is adapted to receive a rotatable screw 53 actuated by an electric geared motor 43 belonging to said electromechanical unit. The rotatable screw 53 is engaged with the corresponding thread of an internally threaded nut or bushing 55 housed within said cavity 49, preferably at said open base 51. Said nut or bushing is co-molded with or press-fitted in the open base 51 of the longitudinally slidable hollow rod 29. The electric geared motor 43 has a driving shaft 57 provided, in turn, with a pinion 59, which, with its teeth, engages into a toothed gear wheel 61 fixed to the base of said screw 53. The electric geared motor 43 is adapted to cause, through coupling between the pinion 59 and the toothed gear wheel 61, rotation of the screw 53 in both directions, depending on the direction of rotation of the electric geared motor, and consequent sliding back and forth of the hollow rod 29.

[0060] According to the invention, the casing 13 of the shell 11 is made of a plastic material, preferably by means of the injection molding technique, and said guide member 27, if provided, is molded during forming of said casing 13 and thus forms a single piece with said casing 13.

[0061] The guide member 27 extends longitudinally preferably outside the casing 13 of the shell 11. In other embodiments, however, it can also be envisaged that the guide member 27 extends inside the casing 13 or both inside and outside said casing.

[0062] Preferably, in addition, the guide member 27 comprises an annular gasket 63 adapted to exert a hydraulic tight-fit action against the outer surface of the rod 29, thus contributing to make the shell 11 substantially waterproof. The gasket 63 is housed, according to the shown embodiment, in an annular groove 65 open radially towards the inside of the cavity 35 of the guide member 27 and longitudinally outside the guide member 27 and is held in position by a locking cap 67, which is axially fitted on the guide member 27 and prevents the gasket 63 from slipping out of said groove 65.

[0063] The guide member 27 is surrounded by said engaging ferrule 23 for the open base of a syringe SR for drug infusion, whereby, when the syringe SR is engaged in the ferrule 23 and the guide member 27 extends outside the casing 13, the guide member 27 extends over a portion of the length of the hollow body of the syringe SR.

[0064] The longitudinally slidable hollow rod 29 comprises a distal portion or pusher 69 provided with an annular portion 69a extending radially towards the outside of the rod 29, and a longitudinal portion 69b extending axially from said annular portion 69a. Said pusher 69 is apt to be received in a seat SD provided in the sliding plunger SF which causes exit of the drug from the syringe SR.

[0065] Said seat SD provided in the plunger SF receives the pusher 69 preferably with some interference, in order to prevent occurrence of the so-called free-flow phenomenon, i.e. the exit of the drug from the syringe also in the absence of infusion by the apparatus, because of the pressure in hydrostatic pressure due to the position in which the apparatus may be arranged relative to the patient's body associated with the apparatus.

[0066] Referring now to FIGS. 4 to 6, there is illustrated a shell 11 according to the invention provided with a protective bell 71 for the syringe SR associated with the infusion apparatus. The bell 71 mainly comprises a pair of half-shells 71a,71b preferably hinged at the base at hinge pins 73. In the illustrated embodiment, the half-shells 71a,71b are hinged to the ferrule 23, which ferrule is in turn preferably incorporated in the body of the casing 13. According to the invention, the half-shells 71a,71b can assume, by rotating continuously around the hinge pins 73, an open configuration (FIGS. 4 and 5), in which the syringe SR is accessible to be inserted into and removed from the shell 11, and a closed configuration (FIG. 6), in which the syringe SR is substantially completely hidden from view. The half-shells 71a,71b have a substantially “C”-shaped cross-section and consequently define inside them, when closed, a corresponding substantially cylindrical chamber 75 to house the syringe SR. Advantageously, the half-shells 71a,71b have on the top, i.e. in the portion opposite to the hinge pins 73, a transverse base 77a,77b with a corresponding recess 79a,79b defining a corresponding passage 79, when the half-shells are closed, for the front end SC of the syringe SR from which the drug comes out during infusion. Advantageously, in addition, the half-shells 71a,71b, when closed, define a substantially oval cross-section and are made in such a way as to be aesthetically incorporated in the body of the shell 11, following the external profile thereof. Said half-shells are also preferably made of plastics, of the same material as the casing. In particular, according to the illustrated embodiment, said half-shells 71a,71b comprise at the base a pair of parallel wings 81 extending parallel to the ferrule 23 in parallel to the opposite major bases 19,21 of the shell 11. Said wings 81 are advantageously made so as to interfere with the outer lateral surface of said ferrule 23, without, however, jeopardizing the smoothness of the opening and closing movement of the half-shells 71a,71b, and so as to advantageously allow to keep the half-shells 71a,71b closed, thus hiding the syringe SR associated with the shell 11. In order to improve locking of the rotation of the half-shells 71a,71b it is also possible to provide one or more locking teeth between said wings 81 and the ferrule 23.

[0067] In addition, said half-shells 71a,71b are preferably made of plastics, of the same material as the casing 13.

[0068] The invention as described and illustrated is susceptible to several variations and modifications, all of which fall within the same inventive principle.