The present invention refers to a de¬ vice intended to serve as basic element for a disposable injector for medications or diagnostic solutions, already containing the fluid for injection, ready for use.

Presently, therapeutic or diagnostic solutions are administered, mostly, by means of syringes, actuated manually or by means of automated devices, the fluid being transferred to the syringes from glass vials or ampules. Conventional syringes present, however, many recognized disadvantages, as the need to fill the syrin¬ ge from a separate vial, a cumbersome and time consuming process, inccluding the risk of contamination and, in ma- ny cases, the plunger can be difficult to manipulate. In the case of infusion protocols, a bottle or a bag contain ing the solution to be administered must be connected the infusion tubing, by insertions of tubing spike thru the stopper in the bottle or to the connection in a bag, add- ing a step to the preparation for use, requiring, also, some degree of dexterity. Many attempts have been made to provide alternative devices to the conventional syrin¬ ges, to overcome their disadvantages, and also thatof the conventional and separately supplyed infusion bags or bo_t ties and infusion tubings.

One type of approach has been to pro¬ vide an injector system with a pre-filled collapsable re¬ servoir with precisely mesured amounts of medication. The se devices have flexible walls, so that its contents can be discharged by compressing or squeezing it. Devices of

this type are exemplified in the following US patents:

Patent No. Patentee

798,093 Dean

1,222,814 Storz

2.618.263 Lakso, et al.

3.099.264 Hubbard 3,114,369 Hall 4,013,073 Cunningham

4,018,222 McAleer et al.

4,130,117 Van Eck

4,475,906 Holzner

4,581,021 Landau et al. 4,955,871 Thomas

5,261,881 Riner

While the above-listed prior art de¬ vices do, in varying degrees, avoid the aforementioned problems associated with plunger-type syringes, they did not found spread application for several reasons , as for example, a lack of providing sufficient physical support for the needle during injection, some present difficulty for self-injection situations, specially for the physi- cally feeble, some present the inability to be used with disposable needles, and also, in devices of this type so me mechanism must be inccluded to prevent escape of the fluid during storage before use adding complexicity and cost. Another problem with some devices of the type con- sidered is the difficulty in injecting only a portion of the container volume, due to the tendence of the contain er wall material to return to its original shape, or me¬ mory, in case of relaxation of the pressure applied, re¬ sulting in the introduction of air or tissue aspiration. In the case of large volumes injections, there has been

a need for systems easy and confortable to operators use, especially in injection procedures requiring extend ed periods of time. In the same way, there has been also a need for simpler infusion systems, ready for use, de- creasing inventory items and adding simplicity.

In the Pat.Appl.PCT/BR94/00007, an in jecting device has been proposed, based on a flexible plastic recipient containing the fluid, ready for use. However, in that device, the fluid discharge element, a luer-lock, demands a screw cap to avoid fluid escape before use , as well as the fluid container pressing pla¬ tes and catchers are made in three separate members caus ing additional manufacturing difficulties.

Aiming to present a more efficient alternative, easier to use and more cost effective as compared to the conventional systems and other proposed devices as those in the above listed Patents, and also that described in the mentioned Application, by means of a single-acting device, it has been developed the pre- sent medication injector.

The invention can be better under¬ stood with the detailed description of the attached sche dules, being:

The figure 1 illustrates an upper view of the basic element of the device, comprising the fluid for injection container (1) made, preferably, of a bent film of neutral, flexible, pressure resistant and autoclavable plastic material, welded at the edges by heat-sealing process. Opposite to the fluid discharge si _^ de it can be made a bend (12) at the container (1) rear- side to decrease the surface area when filled, seen from container (1) rear-side in the detail AA. At the fluid discharge side, it is fixed the rigid plastic ring (2) , with reinforcement wings (3) , in whose internal distal end, opposite to the container (1) side, is fixed the

proximal end of the injection needle (4) . To avoid fluid escape during storage before use, the needle (4) is en¬ closed in a flexible plastic tube (5) , closed at its dis tal end (6) by heat-sealing, to keep air inside the needle (4) , acting as a blockage to the fluid. To keep the needle (4) sterility, it, and its closing tube, are enclosed in an air-tight envelope (7) , with rims (8) to make its opening easier.

In the figure 2 it is observed a la- teral view of the container (1) with the needle (4) fix¬ ed to the rigid plastic ring (2) , the needle (4) enclo¬ sing tube (5) , the air-tight envelope (7) , in a cutaway view, showing the rims (8) to make its opening easier at the time of use. In the figure 3 it is illustrated an upper view of a fluid container (1) for large volumes drip infusion, made by sealing of two neutral, flexible, pressure resistant and autoclavable plastic films, in whose fluid discharge side it is now fixed the drip in- fusion tubing (9) , with its proximal end fixed to the in ternal surface of the rigid plastic ring (2) in the con¬ tainer (1) , eliminating the conventional spike.The need¬ le (4) of the infusion tubing (9) is enclosed in the flexible plastic tube (5) , closed at its distal end (6) , to keep air inside, thus avoiding fluid escape during storage before use. The infusion tubing (9) is enclosed in the air-tight envelope (7) maintaining the internal sterility. For storage inside the envelope (7) , contain¬ ing rims (8) , the tubing (9) is bent, additionally avoid ing fluid escape from container (1) . In the figure, it is noted the bend (10) in the said infusion tubing (9) , proximal to the container (1) . In the detail BB it is showed the infusion tubing (9) at the time of use, with an optional clamp (11) proximal to the container (1) , if desired an additional closure of the said tubing (9) ,

whose drip chamber (40) is simply a cylinder without fi_l ter, installed below an optional one-way valve (70) , as seen in the detail CC. For bi-phasic fluid administration, the tubing (9) can be attached a three-way stopcock (41) to be adapted a syringe (42) , for an initial bolus, as shown in the detail DD. The orifice (43) in the contain¬ er (1) edge opposite to the infusion tubing (9) ,for hang_ ing up, completes the set.

In the figure 4 it is illustrated a lateral view of a mechanical accessory for pressure in¬ jection of large volumes of fluid, in which it is obser¬ ved the lower base element (13) , with a lower pressure plate (14) , connected to an upper pressure element (15) by means of the main link (16) . Part of the upper ele- ment (15) is the upper pressing plate (17) , straight but preferably curved, fixed to the lower face of the ele¬ ment (15) , by means of the pin (18) at its posterior end, with its anterior end connected to the lower face of the said element (15) , by means of the pin (19) , that slides in the guide (20) . In the figure, it is also noted the scale blade (21) , that slides in the slot (22) , that is displaced, on the upper element command, by means of the rod (23) , connected to the scale (21) by the pin (24) , and connected, by the link (25) , to the other rod (26) , connected to the main link (16) . Once the injection is terminated, with the pressing elements (13) and (15) in contact, their separation, and the scale (21) return to its initial position, and also that of the pin (24) , is blocked by means of the curved blade (27) , linked to the scale (21) , by the arm (35) . The extremity of the curved blade (27) contacts the blade (28) , containing saliences (29) on its lower length. To liberate the motion, the curved blade (27) end should be pressed against its me¬ mory, by means of the angled pin (30) . Completing the scale (21) mechanism, there is the arch (31) serving as

restrictor, by means of its contact to an internal tap¬ pet (32) existing in the rod (23) of scale command shown in the detail EE. Between the lower (13) and the upper (15) pressing elements, it is installed the fluid con- tainer (1), for large volumes injections, linked to an injection tubing (44) , by the rigid plastic ring (2). The injection tubing (44) is maintained, on storage before use, in the air-tight envelope (7) , opened in the figure to indicate a preparation for injection. Also,its needle (4) is enclosed in the plastic tube (5) closed at its distal end (6) to keep air inside the tubing, avoiding fluid escape during storage.

In the figure 5 it is illustrated an upper view of the pressing mechanism for large volumes injections, in which it is observed the scale (21) ,under the transparent blade (33) , seen frontally in the detail FF, being noted thcit the scale (21) slides in the guides (22) and (34) . The scale blade (21) is connected to the locking curved blade (27) , by means of the rod (35) slid ing under the blade (28) with saliences (29) on its low¬ er face, whose contact is better observed in the detail GG, in which it is detached the curved blade (27) , the saliences (29) of the blade (28) and the angled pin (30).

The figure 6 illustrates a frontal view of the pressing mechanism, in which it is noted that the upper pressing blade (17) has two pins (18) and (36) , in its posterior end, and other two pins (19) and (37) , that slide in the guide slots (20) and (38) at the anterior portion of the element (15) . In the figure, it is noted the rod (23) having the internal tappet (32) in contact with the limiting arch (31) , that exists in the side of the element (13) . The salience (39) existing on the lower pressing plate (14) of the base element (13) is intended to fit in the orifice (43) of the container (1) .

In the figure 7 it is depicted a mo¬ del of the proposed medication injector,in an upper view in a variant containing a luer-lock (45) made molded to¬ gether with the rigid plastic ring (46) , with its cap (47) . It is observed, also, part of the recipient (1) placed between the two pressing plates (48) upper and (49) lower, the upper catcher (50) linked to the plate

(48) by a link (51) at the borders but not at the center (52) , and the two elements (53) right and (54) left, to keep the catchers in contact and fixed, as shown in the detail HH, where is depicted, in a frontal view, the cat chers (50) upper and (55) lower.

Figure 8 illustrates a lateral view of the injector, showing the fluid container (1) install ed between the pressing plates (48) upper and (49) lower, the catchers (50) upper and (55) lower, behind the luer- lock (45) , for needle adaption, and its cap (47) . It is also depicted a representation of the upper and lower pressing elements, where it can be noted that they are made of two molded pieces, with the catcher (50) and the pressing plate (48) , upper, as one piece with the inter¬ mediary length (51) flexible, constituting the upper ele ment, and the catcher (55) and the pressing plate (49) , lower, as one piece with the intermediary length (56) , flexible, as the lower element. The catchers (50) upper and (55) lower, are kept in tight contact with the front al edge of the container (1) by means of the welded link (54) showed, and the link (53) not visible in the figure. The detail II show, more clearly, a section of the lower element, equal to the upper, showing the catcher (55) , linked, forming one molded piece, to the pressing plate

(49) and the intermediary length (56) .

In the figure 9 it is illustrated an¬ other variation of the device, whose injection needle(4) linked to the rigid plastic ring (2) with reinforcement

wings (3) and enclosed in the plastic tube (5) closed at its distal end (6) , are enclosed in an external plastic tube (57) , to maintain internal sterility. To accomplish this, the cap (57) is threaded, preferably, in a ring set (58) molded one piece with the ring (2) , whose con¬ tact (59) is covered, preferably, by an adhered ribbon (60) to garantee additional safety for sterility. In the figure, it is also noted the container (1) installed bet ween the pressing plates (48) upper and (49) lower, a section of the upper catcher (50) and the catchers con¬ tact fixing elements (53) right and (54) left. It also can be noted that in this model, the upper and lower pressing sets are now made one molded piece, with the up per and lower pressing elements linked by the bent ele- ments (61) right and (62) left, to facilitate the manu¬ facturing process.

The figure 10 illustrates the inject¬ or device in a lateral view, showing the fluid container (1) between the pressing plates (48) upper and (49) low- er, as one piece with the catchers (50) upper and (55) lower, the element (54) left, to maintain the catchers joined, the needle set external cap (57) and the upper and lower pressing elements left link (62) .

The figure 11 depicts an upper view from the pressing element upper, showing the upper press_ ing plate (48) , the upper catcher (50) , made one piece with the intermediary (51) , with a blank spacing(52) and the bent links (61) right and (62) left.

In the figure 12 it is illustrated a representation of the pressing set, being observed that the upper catcher (50) and pressing plate (48) are made one piece with the lower catcher (55) and pressing plate (49) , straight when not installed on the fluid container (1) , linked by the elements (61) right and (62) left, as one piece with the catchers (50) upper and (55) lower.

The figure 13 illustrates the inject¬ or device in an upper view, with a scale for injected vo lu e and speed monitoring, located at sides of the upper pressing plate (48) , being observed the scale window (63) with a slot (64) in which slides the scale needle (65) , indicating the injected volume.

In the figure 14 it is depicted a la¬ teral view of the medication injector, being observed the scale needle (65) at the end of the command rod (66) operating linked to another rod (67) , with the rods (66) and (67) being linked by the link (68) , just resting on the upper face of the lower pressing plate (49) , being the extermity of the rod (67) , opposite to the link (68) pivoting around the link (69) fixed to the lower face of the upper pressing plate (48) . At the moment of inject¬ ion, the pressure applied on the plates (48) and (49) ma kes them to approach each other, forcing the rods (66) and (67) to rotate, making the scale needle (65) , at the end of the rod (66) to slide in the scale slot (64) in- dicating the injected volume.

In the figure 15 it is illustrated an upper view of a variation of the proposed device, now in tended for fluid aspiration purposes, containing a luer- lock (45) with its semi-free ring (71) , connected to the needle (4) and a dust guard (72) , the rigid plastic ring (2) with reinforcement wings (3) , the now empty contain¬ er (1) , under the upper plate (48) with its handle (73) . When the aspiration is terminated, the needle is with¬ drawn and the luer-lock cap (47) closes the device, to protect the content from contamination.

Figure 16 illustrates a lateral view of the device in its aspiration arrangement, being obser ved the now empty container (1) between, and with its u£ per and lower surfaces firmly glued to, the lower face of the upper plate (48) and to the upper face of the lower

plate (49) , having handles (73) fixed at the surface of the plate (48) upper and (74) at the surface of the pla¬ te (49) lower. The extremities, opposite to the luer- lock (45) , respectivelly (75) of the upper plate (48) , and (76) of the lower plate (49) , are made curved and perpendicular to the longitudinal axis of the device, to facilitate a vertical resting position when filled with the aspirated fluid.

Although the invention has been des- cribed and detailed in accordance with the concretions here inserted, many modifications and variances can be made on it, according to the attached claims.