CONNECTING ARRANGEMENT FOR CONNECTING A SYRINGE TO A PUMP FOR DRUG INFUSION

Abstract

A connecting arrangement for connecting a syringe to an electromechanical pump for drug infusion is provided. The syringe comprises a hollow cylindrical syringe body having a first, tapered open end for discharging the drug and a second open end. The syringe body is surrounded by connecting means arranged to firmly connect the syringe to the pump in a removable manner, an axially sliding plunger being housed in the syringe body for causing suction and injection of the drug through the first end. The pump comprises a pump body housing electromechanical members comprising a sliding rod partially projecting out of the pump body to cause sliding of the plunger within the syringe body of the syringe connected to the pump. The pump body being provided with connecting means arranged to receive in an engaging configuration the syringe body. The connecting means provided on the pump body comprise a cylindrical collar axially extending around the sliding rod and being internally provided with engaging elements, the collar defining a sealing end. The connecting means surrounding the syringe body comprise engaging elements arranged to cooperate with the engaging elements provided in the collar for firmly connecting the syringe to the pump in a removable manner. An annular flange extends radially around the syringe body. The flange cooperates with the sealing end defined in the collar to establish a tight sealing between the syringe body and the collar, whereby, when the syringe is attached to the pump, any moisture that may be present in the surrounding environment outside the pump and the syringe attached thereto does not penetrate into the pump body.

Claims

1. Connecting arrangement for connecting a syringe to an electromechanical pump for drug infusion, wherein the syringe comprises a hollow cylindrical syringe body having a first, tapered open end for discharging the drug and a second open end, said syringe body being surrounded by connecting means arranged to firmly connect the syringe to the pump in a removable manner, an axially sliding plunger being housed in the syringe body for causing suction and injection of the drug through the first end, wherein the pump comprises a pump body housing electromechanical members comprising a sliding rod arranged to cause sliding of the plunger within the body of the syringe connected to the pump, said pump body being provided with connecting means arranged to receive in an engaging configuration the syringe body, the arrangement being characterized in that: the connecting means provided on the pump body comprise a cylindrical collar extending axially around the sliding rod and being internally provided with engaging elements, said collar defining a sealing end; the connecting means surrounding the syringe body comprise engaging elements arranged to cooperate with the engaging means provided in the collar for firmly connecting the syringe to the pump in a removable manner, and an annular flange extending radially around the syringe body, said flange being adapted to cooperate with the sealing end defined in the collar in order to establish a tight sealing between the syringe body and the collar, whereby, when the syringe is attached to the pump, any moisture that may be present in the surrounding environment outside the pump and the syringe attached thereto does not penetrate into the pump body.

2. Arrangement according to claim 1, wherein the annular flange radially extends around the syringe body, in a plane perpendicular to the axis of the syringe body.

3. Arrangement according to claim 2, wherein the flange comprises a cross-section lying in a plane parallel to the axis of the syringe and having the shape of an overturned “U” when the syringe is oriented with its front end upwards.

4. Arrangement according to claim 3, wherein said cross-section having the shape of an overturned “U” defines, in the flange, an annular seat adapted to receive the sealing end of the collar.

5. Arrangement according to claim 4, wherein the sealing end of the collar comprises an annular groove radially open towards the outside.

6. Arrangement according to claim 5, wherein said annular groove of the sealing end is adapted to receive a sealing gasket and wherein said annular groove radially extends and the cross-section of the gasket is selected so that said gasket partially radially extends outside the groove for cooperating with the inner surface of the outer wall of the annular seat provided in the flange.

7. Arrangement according to claim 6, wherein said sealing gasket comprises a rubber O-ring.

8. Arrangement according to claim 6, wherein the flange comprises an outer wall that, when the syringe is oriented with its front end upwards, ends at its bottom with a rounded edge.

9. Arrangement according to claim 5, wherein the collar is provided with at least one radial channel communicating the inside of the collar with the outside and wherein said channel houses a porous element made of a material suitable for allowing passage of air and preventing passage of moisture.

10. Arrangement according to claim 1, wherein the engaging elements provided in the connecting means of the syringe and the engaging elements provided in the connecting means of the pump comprise male/female elements, respectively, or vice versa, of a bayonet-type coupling.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Some preferred embodiments of the invention will be described by way of non-limiting example with reference to the accompanying figures, in which:

[0027] FIG. 1 is a longitudinal section of a pump equipped with a syringe connected to the pump through the arrangement of the invention, made in accordance with a first embodiment of the invention;

[0028] FIG. 2 is an enlarged view of a detail of FIG. 1;

[0029] FIG. 3 is a side view of the collar without gasket;

[0030] FIG. 4 is a top plan view of the collar shown in FIG. 3;

[0031] FIG. 5 is a longitudinal section of the syringe shown in FIG. 1;

[0032] FIG. 6 is a longitudinal section of a pump equipped with a syringe connected to the pump through the arrangement of the invention, made in accordance with a first embodiment of the invention;

[0033] FIG. 7 is an enlarged view of a detail of FIG. 6;

[0034] FIG. 8 is a longitudinal section of the syringe shown in FIG. 6;

[0035] FIG. 9 is a top view of the pump shown in FIG. 6 equipped with a syringe.

DETAILED DESCRIPTION

[0036] In all Figures, equal or functionally equivalent parts have been denoted by the same reference numerals.

[0037] Referring to FIGS. 1 to 5, a first embodiment of the invention is shown, where the connecting arrangement is denoted in the whole by reference numeral 11. Connecting arrangement 11 enables the firm and reversible connection of a syringe 13 to a pump 15. Pump 15 is an electromechanical pump and allows drug infusion into the body of a living being by means of syringe 13.

[0038] Syringe 13 comprises a hollow cylindrical syringe body 17 having a first end, or front end, 19. Front end 19 is open and tapered for drug discharge. Preferably, said end 19 is externally equipped with a connecting element 19a, for instance of the “luer-lock” type, for connection of a cannula or outflow element (not shown), generally ending in a butterfly needle inserted into the body of the living being.

[0039] Hollow body 17 has a second open end 21, surrounded by connecting means 23 arranged to firmly connect syringe 13 to pump 15 in a removable manner.

[0040] A plunger 25 is housed within hollow body 17 and is axially slidable for causing suction and injection of the drug through front end 19 of the syringe.

[0041] Pump 15 comprises a pump body 27 internally housing electromechanical members 29. Said electromechanical members comprise a sliding rod 31 that partially projects out of pump body 27 in order to cause sliding of plunger 25 within body 17 of syringe 13 connected to pump 15.

[0042] Moreover, pump body 27 is externally provided with connecting means 33 arranged around sliding rod 31 and capable of receiving the second end 21 of syringe body 17 in an engaging configuration.

[0043] Advantageously, connecting means 33 externally provided on pump body 27 comprise a cylindrical collar 35 axially extending around sliding rod 31. Collar 35 defines a sealing end 39 and is internally provided with engaging elements 37.

[0044] Connecting means 23 surrounding the second end 21 of syringe body 17 comprise engaging elements 41 arranged to cooperate with engaging elements 37 provided in collar 35 for firmly connecting syringe 13 to pump 15 in a removable manner. Moreover, connecting means 23 surrounding the second end 21 of syringe body 17 comprise an annular flange 43 radially extending around syringe body 17 in a plane substantially perpendicular to axis “S” of syringe body 17.

[0045] Flange 43 is adapted to cooperate with sealing end 39 defined in collar 35 in order to establish a tight sealing between syringe body 17 and collar 35. Advantageously, thanks to the cooperation between flange 43 and sealing end 39, a substantially watertight condition is determined when syringe 13 is attached to pump 15. Consequently, any moisture that may be present in the surrounding environment outside pump 15 and syringe 13 attached thereto does not penetrate into pump body 27.

[0046] Sliding rod 31 is driven by electromechanical members 29 of the pump and has in its front part a pushing member 51 arranged to cooperate with plunger 25 of syringe 13. Pushing member 51 includes a cylindrical blind body 51a penetrating into the body of plunger 25, in a seat 25a provided therein.

[0047] In the embodiment illustrated, annular flange 43 radially extends around syringe body 17, in a plane substantially perpendicular to axis “S” of the syringe body.

[0048] In accordance with a preferred embodiment of the invention, flange 43 comprises a cross-section, i.e. a section lying in a plane parallel to axis “S” of syringe 13 when flange 43 is perpendicular to the axis of the syringe body, having the shape of an overturned “U” when syringe 13 is oriented with its front end 19 upwards. Consequently, an annular seat 53 adapted to receive sealing end 39 of collar 35 is defined in flange 43.

[0049] Always in accordance with a preferred embodiment of the invention, sealing end 39 of collar 35 comprises an annular groove 55 radially open towards the outside. Said groove 55 is adapted to receive a sealing gasket 57, e.g. an O-ring made of rubber or similar material. Annular groove 55 radially extends and the cross-section of gasket 57 is chosen so that said gasket 57 partially radially extends outside groove 55 for cooperating with the inner surface of outer wall 59 of annular seat 53 provided in flange 43.

[0050] Preferably, flange 43 comprises an outer wall 59 that, when syringe 13 is oriented with its front end 19 upwards, ends at its bottom with a rounded edge 61. Advantageously, thanks to such an arrangement, premature wear of sealing portion 39 and sealing gasket 57, if any, caused by the interference with flange 43 when syringe 13 is attached to or detached from pump 15, is avoided.

[0051] In accordance with a particular embodiment of the invention, collar 35 is provided with at least one radial channel 63 putting the inside of collar 35 in communication with the outside. Preferably, said channel 63 houses a porous element 65 made of a material suitable for allowing passage of air and preventing passage of moisture. Advantageously, in this manner, the pressure inside collar 35 is maintained equal to the pressure in the external environment, where atmospheric pressure typically exists. Preferably, two diametrically opposite channels 63 are provided.

[0052] Engaging elements 41 provided in connecting means 23 of syringe 13 and engaging elements 37 provided in connecting means 33 of pump 15 preferably comprise respective elements of a bayonet-type coupling 67, 69. Preferably, engaging elements 41 provided in the connecting means of syringe 13 are female elements, i.e. annular grooves 67 formed in the outer wall of syringe body 17, and engaging elements 37 provided in connecting means 33 of the pump are male elements, i.e. annular radial teeth 69 projecting inside collar 35. Preferably, two said engaging elements 37, 41 are provided, which are diametrically opposite and extend over an arc of circumference of about 30°.

[0053] In the embodiment illustrated, connecting means 33 of pump 15 are formed on a ferrule 71 closing one face of pump body 27. The base of ferrule 71 has an opening 73 for the passage of rod 31 partially projecting out of pump body 27 and extending outside in order to exert the push on plunger 51. A sleeve 75 is provided around opening 73 and it acts as an engaging element for a first end of an extensible bellows 77 surrounding rod 31. A second end of bellows 77 engages into a corresponding sleeve 79 provided inside pushing member 51. Said bellows 77 assists in protecting rod 31 and prevents liquids, e.g. the drug, from arriving in contact with rod 31 and penetrating into pump body 21, thereby negatively affecting the regular operation of pump 15.

[0054] Referring to FIGS. 6 to 9, a second embodiment of the invention is shown. In this embodiment, collar 35 substantially extends over the whole length of syringe 13. Consequently, flange 43 is defined in correspondence of front end 19. Advantageously, in accordance with this embodiment, syringe 13, when it is attached to pump 15, is substantially housed within collar 35.

[0055] In accordance with the invention, flange 43 is adapted to cooperate with sealing end 39 defined in collar 35 in order to establish a tight sealing between syringe body 17 and collar 35. Advantageously, thanks to the cooperation between flange 43 and sealing end 39, a substantially watertight condition is determined when syringe 13 is attached to pump 15. Consequently, any moisture that may be present in the surrounding environment outside pump 15 and syringe 13 attached thereto does not penetrate into pump body 27.

[0056] In the embodiment illustrated, annular flange 43 radially extends around syringe body 17, in a plane substantially perpendicular to axis “S” of the syringe body.

[0057] In accordance with this embodiment of the invention, flange 43 comprises a cross-section, i.e. a section lying in a plane parallel to the axis of syringe 13 when flange 43 is perpendicular to axis “S” of the syringe body, having the shape of an overturned “U” when syringe 13 is oriented with its front end 19 upwards. Consequently, an annular seat 53 adapted to receive sealing end 39 of collar 35 is defined in flange 43.

[0058] Always in accordance with this embodiment of the invention, sealing end 39 of collar 35 comprises an annular groove 55 radially open towards the outside. Said groove 55 is adapted to receive a sealing gasket 57, e.g. an O-ring made of rubber or similar material. Annular groove 55 radially extends and the cross-section of gasket 57 is chosen so that said gasket 57 partially extends radially outside groove 55 for cooperating with inner surface of outer wall 59 of annular seat 53 provided in flange 43.

[0059] Preferably, flange 43 comprises an outer wall 59 that, when syringe 13 is oriented with its front end 19 upwards, ends at its bottom with a rounded edge 61. Advantageously, thanks to such an arrangement, premature wear of sealing portion 39 and sealing gasket 57, if any, caused by the interference with flange 43 when syringe 13 is attached to or detached from pump 15, is avoided.

[0060] In this embodiment, pump 15 comprises a pump body 27 internally housing sliding rod 31 being part of electromechanical members 29 of pump 15. In this embodiment, rod 31 remains therefore within collar 35 of pump body 27 during the sliding of plunger 25 caused by the sliding of rod 31.

[0061] In this embodiment, front end 19 of syringe 13 further comprises a second flange 91 provided with radial projections 93 making grip by the user easier. A pair of diametrically opposite teeth 95 is provided, radially projecting from the second flange 91. Teeth 95 are arranged to interfere with an abutment 97 provided in pump body 27 and having a curved end 97a, defining a stop edge 97b. Interference between one of teeth 95 and said end 97a determines the desired sensation of proper connection of syringe 13 to pump body 27 when syringe 13 is turned for being attached to the pump.

[0062] In the embodiment illustrated, the second flange 91 is adjacent to the first flange 43 and both flanges are integrated into syringe body 17.

[0063] Hollow body 17 of syringe 13 has a second open end 21 where engaging elements 41 are provided, arranged to cooperate with engaging elements 37 provided at the base of collar 35 for firmly connecting syringe 13 to pump 15 in a removable manner.

[0064] Engaging elements 41 provided in connecting means 23 of syringe 13 and engaging elements 37 provided in connecting means 33 of pump 15 preferably comprise respective elements of a bayonet-type coupling 67, 69. Preferably, engaging elements 41 provided in the connecting means of syringe 13 are female elements, i.e. annular grooves 67 formed in the outer wall of syringe body 17, and engaging elements 37 provided in connecting means 33 of the pump are male elements, i.e. annular radial teeth 69 projecting inside collar 35. Preferably, two said engaging elements 37, 41 are provided, which are diametrically opposite and extend over an are of circumference of about 30°.

[0065] The connecting arrangement as described and illustrated can undergo several changes and modifications, falling within the same inventive principle.