FR2671729A1 - DEVICE FOR DELIVERING CONTROLLED DOSES, PARTICULARLY OF THE DISPOSABLE INSULIN SYRINGE TYPE. - Google Patents

Abstract

The device for administering controlled doses is comprised of an elongate hollow body (2) appropriate to be housed inside a refill of fluid product, actuated by pushing a pusher slidingly mounted within the body (2) on the upstream side of the refill, by means of a pushrod (40), limiter means (23, 29) to limit the authorized excursion of the pusher (4) towards the refill, and anti-return means (55) for the pusher. The push-rod (40) has a cylindrical or prismatic shape, and the anti-return means is comprised at least of a semi-rigid wing inclined to the axis (55) cooperating in a buttressing way with the side surface of said pushrod (40).

Description

Device for delivering controlled doses, in particular for disposable insulin syringe
The invention relates to the delivery of controlled doses of a fluid product, that is to say liquid or pasty.

Although it is capable of very numerous applications in various fields, it is of particular interest for repetitive injections carried out by the patients themselves, as is the case in particular for certain patients with insulin.

Such a device for delivering controlled doses is already known, comprising - an elongated hollow body suitable for internally housing a refill of a liquid or pasty product, actuated by pushing, as well as for receiving on the downstream side of the refill a nozzle for delivery, - a pusher mounted to slide in the body on the upstream side of the refill, with a push rod, - means limiting the excursion allowed to the pusher towards the refill, to define the dose.

The known devices are for the most part very complex in structure. Their constitution is therefore hardly compatible with the concept of disposable syringe, which is essential for various reasons: to avoid contamination in the medical field, or more simply approval of use, if it is for example the distribution of glue.

Furthermore, most of the known devices require a new definition of the dose for each use. This complicates its use, and involves risks of errors during medical applications.

It is also necessary for the definition of the dose to be precise, and preferably verifiable by several means, including for example acoustic means for the blind.

Finally, it may happen that during the definition of the dose, the user no longer knows where he is. This can lead to incorrect dosing or even damage to the device.

The main object of the present invention is to provide suitable solutions to the difficulties noted above.

According to a first characteristic of the invention, the push rod is of cylindrical or prismatic shape (in principle smooth) and the non-return means comprises at least one semi-rigid fin inclined on the axis, and cooperating with bracing with the lateral surface of said push rod. By semi-rigid fin means a fin which is inherently flexible due to the bracing. It turned out that this non-return means already considerably simplifies the construction of the device.

In practice, the fin or fins form a non-return upstream for the push rod relative to the body. Preferably, this push rod cooperates with a plurality of regularly distributed fins, converging towards the center in the direction of the end piece of the device, with a geometry corresponding to that of the cross section of the rod. Thus, the fins provide, at the same time as the non-return function, that of holding the rod inside the body.

This maintenance is even better ensured when the characteristic of the invention below is used.

According to this, the pusher also cooperates with the push rod by means of at least one other semi-rigid fin, preferably a plurality of fins, inclined on the axis, and cooperating with bracing with the lateral surface of the push rod, so as to also form non-return, but this time downstream, for the pusher relative to the rod.

Preferably, this or these other fins, regularly distributed, converge towards the center in the direction of the end piece of the device, with a geometry corresponding to that of the cross section of the rod. Thus, these fins, at the same time as the non-return function, contribute to the maintenance of the rod inside the body.

This second set of fins is in principle mounted on the same support. This can also be made deformable, by pivoting around an annular guideline, so as to favor the return upstream of the second fins relative to the rod. We can thus order the implementation of a new dosage. Insofar as the pusher returns upstream with these second fins, the current dose is memorized, if desired.

It is also advantageous to provide braking means, forming a non-return upstream of the second fins relative to the body. Preferably, an elastic compression force is exerted between these second fins and the body.

Other characteristics and advantages of the invention will appear on examining the detailed description below, as well as the appended drawings, in which - Figure 1 is a longitudinal sectional view of a device according to the invention; - Figure 2 is an enlarged partial view corresponding to the right part of Figure 1, where appears most of the means according to the invention; - Figure 3 is a simplified diagram to facilitate the understanding of the mechanisms visible in Figures 1 and 2; - Figures 4 and 4A are two partial perspective views detailing the structure of the non-return means with metal fins, in two respective embodiments; - Figures SA to 5C illustrate a particular embodiment of the push rod; - Figures 6A to 6D illustrate a particular embodiment of the sleeve; - Figures 7A to 7C illustrate a particular embodiment of the body of the device, in its right part; - Figure 8 illustrates a first embodiment of the ring with its lever; - Figures 9A to 9D illustrate a particular embodiment of the ring with its lever forming a braking device and notched action; - Figures 10A to 10C illustrate an alternative embodiment of the fins 55 and the lever 70; and - Figures liA and liE illustrate another alternative embodiment of the fins 55, in two parts.

The accompanying drawings are essentially of a certain nature.

Consequently, they are to be considered as integral parts of the present description, and could serve not only to make it better understood, but also to contribute to the definition of the invention, if necessary.

The detailed description below relates to the case of a drug injection. We will henceforth call the device "syringe"
In Figure 1, the syringe comprises in the left part a housing 1 containing a cartridge or cartridge 3 containing for example insulin. This cartridge is provided, at one end, with an actuating piston 34, and at the other with a head 32 housing a seal passable by a needle. A needle holder (not shown) can be fixed at 12 to the housing 1. The means 12 can be a thread or other fixing means.

The housing 1 is fixed by gluing, crimping or any other means on the rest 2 of the body (which will be called "the body" below).

This body 2 (Figures 1, 2 and 7A to 7C) comprises, on the left a cylindrical part 21, followed by a central part provided with a longitudinal notch 22 (there is seen in Figure 7C the lever 70). After that, the body 2 offers an internal radial shoulder 23. On the other side of the shoulder, that is to say on the right, it defines at 24 a housing, which can be provided with longitudinal grooves 24A (figure 7B).

 The pusher essentially consists of three main parts: a push rod 40, a sleeve 50 and a ring 60.

In order to facilitate the description, the thrust rod will be considered hereinafter as being external to the pusher assembly, although it naturally contributes to the thrust function.

This push rod 40 (Figures SA to 5C) has a polygonal cross section, for example square with cut corners (Figure 5C).

At one end, an enlarged end piece 42 comes in one piece with the rod 40. At the other end is provided an added end piece 41.

The sleeve (FIGS. 6A to 6D) is designated as a whole by 50. An external central shoulder 53 separates it into two parts 51 and 54, of generally cylindrical shape. Its right-hand part 51 is provided with an external thread 52, and with a reinforced end 58, adapted to rotate relative to the rod 40.

In parts 51, 53 and 54 are cut longitudinal lips 57A and 57B. These support a nipple 57 with elastic return to the outside. By cooperation with the axial grooves 24A of the body (FIG. 6C), this stud realizes an indexing of the rotation of the sleeve, at the same time as an audible indication.

It is added on the right to the sleeve 50 a cap 59 serving simply to facilitate the rotational drive thereof.

The ring 60 (FIG. 8) is in the form of an elongated cylinder, of circular cross section. But there is provided at the top a recess 63, on which comes, as an integral part and projecting longitudinally, a lever 70. Internally, the ring is provided with a thread 64 adapted to cooperate with the thread 52 of the sleeve. The lever 70 projects overhanging in the axis above the ring.

A variant of the ring is illustrated in FIGS. 9A to 9D. Here, the body 61 of the ring has a flat portion 62 at the top. The lever 70 has a special shape. On the side of its end (towards the left in the figures), it is split into two parts 71 and 72, which define notches 75 and 76.

Corresponding notches 27 and 28 are provided on the notch 22 of the body. While the notching of the body at 27 and 28 (FIG. 9D) is symmetrical, it is noted that the notches 75 and 76 of the lever are offset by half a step.

In addition, there is provided, on the lever, at the level of these notches, a rift making it possible to act with a finger, such as the thumb, on the lever 70 for purposes which will be described later.

We now return to FIGS. 1 and 2. The right part 2 of the body is completed with superimposed parts 29, ensuring the exact housing of the sleeve 50, while defining an upstream stop for the latter, opposite to the downstream stop 23 already described.

On the side of the left end of the body 2, it accommodates a plurality of fins 25, which bear on the rod to form non-return upstream, that is to say to the right. In other words, once the rod has been pushed in, it cannot go back.

At the left end of the ring 50 is also fixed a set of fins 55, which also bears on the rod. This set of fins essentially has the function of controlling the advancement of the rod by pushing the ring.

The fins 55 (FIG. 4) have come here as a material on a metal ring, advantageously provided rearward with an axial tongue 56. The periphery of the ring and / or the tongue 56 may be embedded in the synthetic material of the ring 50. The ring 50 is for example overmolded on these metal parts.

Alternatively, the periphery of the ring and / or the tongue 56 can be embedded in the synthetic material of the lever 70, for example by overmolding. In this case, the tongue 56 can form a brake, by its corners which engage on the internal wall of the body 2. Other embodiments of the brake can be envisaged.

In FIG. 3, it can be seen in a simplified manner that at rest the shoulder 53 of the sleeve comes to bear on the downstream stop 23 of the body. This is the zero dose, in the embodiment described.

Unscrewing the sleeve relative to the ring makes it possible to fix a dose. To this end, precise indications can be given on the side of the control button 59, with for example display of visual indications at the level of the window visible at 59A in FIG. 1.

After fixing the desired dose, the shoulder 53 has therefore deviated by a certain distance from the shoulder 23.

The limit excursion is defined by the left shoulder of part 29.

When the button 59 is now pressed, the sleeve 50 and ring 60 assembly will advance to the left, and the non-return means 55 will push in correspondence the rod 40, hence the actuation of the piston 34 to deliver the dose wanted.

As the ring advances, the lever 70 (Figure 8) does the same, and progresses in the notch 22 of the body. This movement is carried out against the elastic return provided by the spring 69.

Two cases can then arise: - or else the spring 69 is weak, in which case its return is not sufficient to return the sleeve 50 - ring 60 assembly to its starting position; by the lever 70, acting on the tongue 56 associated with the fins 55 (FIG. 4), the user makes the fins 55 rotate annually, which facilitates the upstream return, which the user helps with the lever 70.

- Or the spring 69 is strong, and its return is sufficient to return the sleeve 50 - ring 60 assembly to its starting position; in this case, the tongue 56 associated with the fins 55 (FIG. 4A), is provided with a widening (to the right of the figure, ie upstream) which causes it to come into engagement by its points on the body, forming a non-return upstream.

The effect of the spring is then braked or blocked. By acting on the lever 70, the user will not only rotate the fins 55 annularly, but also erase the grip of the corners of the tongue 56 on the body. The effect of the spring 69 is then exerted, and produces the upstream return, which the user follows with the lever 70.

After such an injection, it is possible to act again by rotating the sleeve, to order a new dose, equal to the first or different from the latter.

The above refers to the production of the lever 70 according to FIG. 8.

In the variant of FIG. 9, the lever 70 follows the movement of the ring during the delivery of the dose, hence a visual indication as well as an audible one (by the notches) of the actual injection dose. At the end of delivery, the same notches hold the sleeve 50 - ring 60 - lever 70 assembly in the depressed position.

According to this variant, a push on the lever 70, towards the inside of the body, will first have the effect of releasing the notches of the lever from those of the body, then of urging the longitudinal tongue 56 (FIG. 4) of the fins 55 , to print a slight rotation on its annular guideline to the support of the fins, hence a relaxation of the pressure of the fins 55 on the rod, and consequently the return, under the effect of the elastic return 69, of the ring and of the sleeve to their previous position, before injection, and with the same dose as above.

 The assembly used has another advantage: it can happen that after having started to unscrew the sleeve, the user no longer knows exactly where it is. It then suffices for him to eject, as lost, the unknown dose, and to repeat the operation.

Likewise, if an injection has been given only partially, it is possible to determine the quantity actually injected. We can then perform immediately after the desired complementary injection.

For the assembly of the syringe, the body is preferably in two parts 21 and 22, pressed one on the other up to the separation line 28, leaving the clearance of the notch 22.

The assembly of the syringe is carried out as follows - Introduction of the ring 60 from the right into the part 22, until it comes to the stop 23.

- Installation of the fins 55, introduction of the spring 69, and installation of the fins 25.

- Insertion of the part 21 on the part 22 with bonding, to complete the body 2.

- Introduction of the rod 40 from the right until it extends well beyond the left, then fixing of the head 41 on the rod 40.

- Introduction of the sleeve 50 from the left into the part 22, with engagement on the thread of the ring 60, then fitting of the part 29, as well as of the cap 59.

- Attachment of a nozzle 1 housing the desired cartridge 3 at the left end of the body 2.

Of course, the present invention is not limited to the embodiments or assembly described.

For example, the fins 55 (fig. 10C) can be provided with a tongue 56 which is folded in a V (fig. 10A and 10B) to ensure the braking action by its corners 56H and 56L which engage on the inner wall of the body 2.

Another variant consists in doubling the non-return action and the braking action. The fins 55 (fig.llA) provide only the non-return action on the rod 40. An additional part 55B, 56B (fig. LiA and 11B), placed against the part 55, ensures the braking action. The tongue 56B is folded. Its corners brake by pressing on the body 2.

 In both cases, the lever 70, depressed, stops the braking action.

Furthermore, at 25 and 55, two opposite fins, or even one, can be provided instead of the four described. By bending the end of the fins, a curved cross section of the rod 40 can be accommodated.

It is also possible to carry out kinematic inversions: in the description above, the spring 69 opposes the injection, and a brake makes it possible to control either the repetition of the same dose, or a new dosage; conversely, it can be envisaged that the definition of the dose is made by unscrewing the sleeve against an elastic return, with blocking by a brake, the release of which would produce the injection, possibly assisted by hand by the operator , depending on the force of the spring.

Claims (17)

Claims 1.- Device for delivering controlled doses, comprising - an elongated hollow body (1,2) capable of internally housing a refill (3) of a fluid product, actuated by pushing (34), as well as receiving (12) on the downstream side of the refill (3) a delivery nozzle, - a pusher (4) slidably mounted in the body (2), on the upstream side of the refill, with a push rod (40), - limiting means (23,29) of the permitted excursion of the pusher (4) towards the refill (3), and - a non-return means (25,55) of the pusher, characterized in that the push rod (40) is cylindrical or prismatic shape, and in that the non-return means comprises at least one semi-rigid fin inclined on the axis (25,55) cooperating with bracing with the lateral surface of said push rod (40). 2.- Device according to claim 1, characterized in that the or the fins (25) form non-return upstream for the push rod (40) relative to the body (2). 3.- Device according to one of claims 1 and 2, characterized in that the push rod (40) cooperates with a plurality of fins (25), regularly distributed, converging towards the center towards the tip of the device (1), these fins ensuring, at the same time as the non-return function, that of holding this rod (40) inside the body (2). 4.- Device according to one of claims 1 to 3, characterized in that the pusher (4) cooperates with the push rod (40), also by means of at least one other semi-rigid fin (55 ) inclined on the axis (5) cooperating arcboutement with the lateral surface of said push rod (40), and forming a non-return downstream for the pusher (60) relative to the rod (50). 5.- Device according to claim 4, characterized in that the pusher (4) cooperates with a plurality of fins (55), regularly distributed, converging towards the center towards the tip of the device (1), these fins ensuring, at the same time as the non-return function, that of holding the rod (40) relative to the pusher (4). 6.- Device according to one of claims 4 and D, characterized in that the or said other fins (55) are mounted on the same support (56), deformable on command to promote their return upstream. 7.- Device according to claim 6, characterized in that it comprises an actuating lever (70) of the deformable support, mounted in a longitudinal notch of the body (22), accessible from the outside. 8.- Device according to one of claims 4 to 7, characterized in that the or the fins (55) are integral with braking means (75,76) forming non-return upstream of these fins relative to the body. 9.- Device according to claim 8, taken in combination with one of claims 6 and 7, characterized in that the braking means are also produced by the support (56) deformable. 10.- Device according to one of claims 4 to 9, characterized in that the said other fin (s) (55) are mounted on the same support (56), subjected to an elastic compressive force with respect to the body (2) . 11.- Device according to claim 10, characterized in that the elastic return (69) is exerted between the fins (55) and the body (fins 25), upstream. 12.- Device according to one of claims 4 to 11, characterized in that the pusher (4) comprises a sleeve (50) and a ring (60). 13.- Device according to claim 12, characterized in that the or said other fins (55) are integral with the ring (60). 14.- Device according to one of claims 12 and 13, characterized in that the sleeve (50) is provided with a shoulder (53), movable on one side of a stop (23) of the body.  15.- Device according to one of claims 12 to 14, characterized in that the sleeve (50) is provided at least in part with peripheral thread sections (52), while the ring (60) is provided with sections thread (64) cooperating with those of the sleeve, the rotation of the sleeve (50) with translation relative to the ring (60) allowing the fixing of a dose. 16.- Device according to one of claims 12 to 15, characterized in that the sleeve comprises, on its periphery, notched means forming noise and / or visual indicators. 17.- Device according to one of the preceding claims, characterized in that the body (2) is produced by at least one part, which can be assembled on the housing (1) of the refill (3).