KR100426154B1 - Disposable syringe with intake mechanism - Google Patents

Abstract

The present invention relates to a disposable syringe 10 having a rod-type plunger 14 having a plurality of truncated-conical or beaded ratchet teeth 28 formed therein. A radially elastic spring lock clip 40 is engaged on the ratchet portion of the plunger. The position of the clip determines the maximum dosage that can be administered by syringe. Intake gap 114 may be provided on the plunger rod to allow for selective intake before loading and delivering the drug. During use, the first withdrawal of the plunger to the barrel 12 allows intake, and then the drug is released from the barrel as the cam teeth 83 of the spring locking clip slide over the surface of the ratchet teeth by bending radially. It can be injected into the cavity and the locking spring is held in a relative position along the barrel by outwardly oriented contacts embedded in the inner sidewall of the barrel.

Description

Disposable syringe with intake mechanism

The present invention generally relates to hypodermic needles and syringes, and more particularly, can be used to convert plastic hypodermic syringe barrels into inexpensive and difficult to use disposable syringes made from already medically applied materials. A spring lock clip and associated plunger. For the purposes of the present invention, the term disposable means that the maximum dosage placed in the syringe is that amount that can be administered only once. However, the syringe can dose the drug multiple times and deliver on each dose only a portion of the total drug that can be pulled into the syringe by pulling it completely towards the plunger rod at one time close to the syringe barrel. For the sake of simplicity, the term disposable refers to the amount that is fully dispensed at one time of the total drug in the barrel and includes one or more uses where each use delivers a dosage less than the maximum. The total cumulative amount of delivered dose obtained when fully used should not exceed the maximum dose or the total dose injected into the syringe by one backward reciprocating movement of the plunger rod relative to the barrel. The syringe is a disposable syringe in which the maximum or total dose of the syringe (determined by the position of the spring clip on the plunger and / or the barrel dose) is fully dosed in a single use at first. In such a case, the spring clip moves to the furthest position, and all reuse is prevented. If an amount less than the maximum dose injected into the barrel is delivered in the first or subsequent dose delivery, the subsequent dose administered must be less than the maximum dose. To administer a drug that is configured to be administered separately, the plunger rod can be moved to the distal end only once. The sum of all drugs administered may not exceed the single dosage dose of the syringe barrel. In this way, the device is a "disposable" syringe.

Disposal after safe single use of hypodermic needles and syringes is a matter of concern in the medical and health sectors. Concomitant needle inflammation following the use of syringes presents a serious risk to patients, doctors and nurses. This risk is a source of great concern due to current HIV and hepatitis inflammation, a concern of the general public. Therefore, careful attention should be paid to the safe handling and disposal of the needles and syringes used. To this end, the present invention represents a disposable injection needle and syringe assembly. Once the injection needle and syringe (hereinafter collectively referred to as 'injector') are used, the instrument of the present invention excludes further use. Therefore, it is easier to dispose of properly than if it was possible to use it further. Cross-infection from patient to patient and the possibility of cross-infection from drug users to drug users are reduced.

The present invention can be compactly implemented with a very small barrel dose syringe, including a syringe capable of administering a small dosage of about 0.1 cc. On the other hand, the prior art described in more detail below cannot be easily and economically miniaturized while maintaining the efficiency of single use, which is the only mechanism they described, and therefore, they are smaller in size than standard 3 cc syringe bodies. Was not introduced commercially. The initial axial position of the locking mechanism relative to the syringe barrel of the disposable syringe of the prior art was a means for limiting a conventional 3 cc syringe to a maximum of 1 cc dosage. However, if the locking mechanism, ie the position of the clip as well as the size of the syringe, determines the maximum dosage, it is clearly desirable for the syringes to have a smaller maximum dosage. However, although the present invention may be adapted for use with 3 cc or other maximum dosage syringe barrels, it should be appreciated that the present invention is particularly applicable to syringes with a dosage of barrels as low as 0.1 cc dosage.

In general, inexpensive syringes are recognized to meet the needs of underdeveloped countries and contribute to the reduction of global sanitation costs. Low cost can alleviate the syringe reuse problem currently faced by disposable syringes. Cross infection resulting from the reuse of the same syringe from one patient to another can only be observed by a disposable syringe. It also reduces the patients' concern that it may result in a potential infection suspected from previous syringe use.

The present invention provides a simple and inexpensive instrument for limiting the use of syringes (with or without injection needles) to one time, ie only one use. Such a syringe is intended to be assembled at a manufacturing facility and provided to the physician (or nurse, patient, etc.) to use it. The user fills the syringe with the appropriate drug in a conventional manner, ie withdrawing the plunger against the cylindrical barrel of the syringe and introducing the drug into the chamber of the barrel through the tip of the injection needle. According to the invention, the plunger may be repeatedly reciprocated to intake before filling the drug. If the user determines that the intake reciprocating momentum is sufficient, the positive movement of the plunger relative to the barrel ensures the operation of the disposable locking mechanism. Thus, again, as in the prior art, an injection needle is inserted through the patient's skin. The plunger is manually moved relative to the cylindrical barrel to press the piston towards the distal end of the syringe. The piston pushes the drug out through the tip of the injection needle.

During the dosage administration of the process according to the invention, as will be explained in more detail below, the spring locking clip moves with the plunger axis and, when reaching the distal position, the locking point or contact with the base of the spring locking clip It is held on the inner sidewall of the cylindrical barrel by the contacting piston. Shrinkage of the second attempted plunger against the cylindrical barrel of the syringe is prevented. Thus, no further drug can be injected into the syringe, and thus the syringe cannot be used again. Simple and inexpensive disposable syringes are provided. The locking mechanism that excludes reuse is automatic, i.e. acts to prevent it from being unintentionally reused after inhalation by the user to ensure its operation.

The design of an economically productable syringe assembly that has a disposable feature and ensures its safety or disposable operation is a reality of numerous patients and efforts. Such syringes should be easy to manufacture and assemble, function in a standard manner, be able to deliver fluids of various volumes, use materials commonly applied for medical use, and preferably for use in making syringes currently in use. Standard manufacturing equipment is required, and importantly, the cost must be low.

The present invention achieves this object by using a new and unique plunger which is associated with a new and unique spring locking clip. Such plungers comprise a plurality of cylindrical, ie frusto-conical ratchet teeth, or in other embodiments bead. The spring clip is positioned by the manufacturer at a specific location along the axis of the plunger to limit the maximum withdrawal of the plunger, ie the dosage of the syringe accordingly. According to a preferred embodiment of the present invention, a longitudinal space is provided between at least two ratchet teeth or beads. This space allows the plunger to withdraw and advance without the associated spring clip. This makes it possible to inhale the syringe before loading the drug into the barrel. In addition, the use of bead-shaped ratchet teeth instead of the previously described truncated-conical ratchet teeth allows for smoother operation during withdrawal of the plunger, as in the prior art apparatus. The force required to withdraw the plunger is significantly reduced compared to the plunger's in output when the ratchet teeth are conical or frusto-conical.

At present, details on the maximum withdrawal power of the plunger in a hypodermic needle / syringe are known. This was established by the International Standards Organization. Applicant's disposable syringe designs, the subject of US patent application 08 / 195,302 filed February 14, 1994 and US patent application 08 / 232,749 filed April 25, 1994, were tested and three major Although the unit has a plunger in power below the maximum limit of the standard, it has been found in some units to slightly exceed the details. In order to ensure a high quality product that always meets the above standards, the present invention has been developed. Of course, as an alternative, since the "standard" of the present invention satisfies disposable syringes that are intended to be used repeatedly and that can be used repeatedly, a new standard maximum plunger in-output could be established for disposable syringes.

According to a preferred aspect of the invention, the ratchet teeth of the plunger are "bead shaped". When the plunger rod is withdrawn, the spring clip does not follow each ratchet tooth discontinuity, unlike the device shown in Applicant's prior patent application. Rather, the beads allow the spring clip to slide more smoothly on the surface of the beads. It has been found that the withdrawal is reduced and becomes about the same as for plungers and reusable syringes without spring locking clips.

Preference is given to multiply aspiratable syringes with spring locking clips. The invention described in the prior patent application is not designed to allow multiple intakes (i.e. multiple reciprocating motions of the plunger to draw air into the barrel and then eject it from the barrel), and the initial withdrawal and withdrawal of the plunger is the furthest forward position In the case of advancing the spring clip at a position short of this, a limited range of intake was possible.

The present invention is intended to allow multiple intakes. The device of the present invention uses a gap between the ratchet teeth so that when the spring clip is positioned between the ratchet teeth, ie within the gap, no movement of the plunger will advance the spring lock clip. Of course, the size of the gap between the ratchet teeth determines the amount of intake air.

The use of these new plungers and spring locking clips prevents the reuse of syringes. The structure can be incorporated into a 0.1 cc barrel size syringe without any loss of efficiency or safety. According to the operating mechanism of the present invention, an extremely small volume syringe can be manufactured without loss of function. In contrast, very small volumes of syringes cannot be manufactured because the locking mechanisms of the prior art disposable syringes operate by using different instruments. The present invention is economically manufactured, has tamper resistant properties, administers drugs using conventional techniques, can be made from medically approved materials, and can be made with standard equipment.

The present invention has a plunger withdrawal within the acceptable limits of a syringe used multiple times, but is a disposable syringe. Mechanical withdrawal of the plunger with the beaded teeth works more smoothly than the operation indicated by the truncated-conical ratchet teeth. In addition, the use of one or more intake gaps between the ratchet teeth allows the syringe to selectively and repeatedly inhale.

A feature of the present invention is that by providing a break-apart disc with the thumb contact of the syringe plunger, after use, the user of the syringe may simply bend, twist, or remove the disc in contact with the thumb. And thereby makes it impossible to reuse the syringe further. Ease of removal from the syringe of the thumb contact of the plunger shaft also serves as a means to track the inventory of the syringe.

Various attempts described in the patent literature and other publications generally describe a mechanism for providing a disposable syringe without considering geometric limitations such as the minimum total volume that the syringe barrel can contain. It is evident that there are some minimum volume limitations in disposable syringes that not only rely on design but also on the limitations on productivity resulting from small size. In practice, when a small amount of drug is injected, it is desirable to use a syringe with a reduced overall volume rather than limiting the operation of larger barrel dose devices as both the accuracy and ease of use are increased. In contrast to the prior art, the present invention uses entirely different mechanisms and forces to prevent syringe reuse. Thus, extremely small volume syringe structures can be achieved.

To date, safe syringes have been manufactured that provide some degree of protection against accidental needle infection. These designs require relatively complex instruments or have relatively large volumes. Often, these designs are relatively expensive to manufacture. Most prior art disposable restriction instruments are intended for use with standard X-shaped plungers of conventional syringes. On the other hand, the present invention contemplates the use of an entirely new plunger based on a rod consisting of ratchet teeth, preferably bead teeth. Moreover, activation of safety features of prior art instruments can sometimes fail or be intentionally stopped. The present invention is believed to be more effective in preventing the reuse of syringes.

However, particularly importantly, as described above, the present invention can be incorporated into syringes of suitable dimensions even for a maximum dosage of 0.1 cc, very efficiently and inexpensively. In this way, the device can be incorporated into a very low dosage syringe. This is very desirable. In contrast, disposable or "safe" syringes of the prior art cannot or cannot be reduced in size. These prior art syringes are not commercialized at a maximum dosage of 0.1 cc, but rather, manufacturers use standard larger barrel syringes (eg 3 cc) and the degree of movement of the plunger shaft to limit the maximum dosage. Restrict It is a particular object of the present invention to provide a disposable syringe with a maximum capacity as low as 0.1 cc which is mainly achieved by the reduction of the barrel, not by the position of the spring locking clip.

The preceding approaches to the design of disposable plastic syringes are classified as follows:

(a) locking the plunger after delivery;

(b) separation of the plunger;

(c) withdraw the needle into the syringe barrel after dose delivery;

(d) physical destruction of a portion of the syringe;

(e) chemical means to render the syringe unusable after initial use; And

(f) Use of auxiliary means such as sleeves to provide syringe needle-stick protection and at the same time prevent the reuse of syringes.

The syringe of the present invention utilizes a mechanical method to prevent further use of the plunger by the novel spring lock clip mechanism as follows.

Prior art locking mechanisms generally operate by means of a conventional X-type plunger, optionally by a cylindrical plunger. In the use of an X-type plunger, this plunger is held in axial alignment with the axis of the barrel by the X-shaped edge of the plunger. In using the locking device on the cylindrical plunger, the locking device extends generally symmetrically around the plunger. Thus, these plungers were kept in axial alignment with the barrel. In the X-shaped plunger with the locking clip device of the prior art and the cylindrical plunger with the locking clip around, the axial alignment between the barrel and the plunger excludes a potential desirable reduction in the maximum capacity of the syringe.

On the other hand, the present invention basically uses a new locking mechanism for the cylindrical plunger. The structure and manner of operation of the spring locking clip of the present invention results in a radial displacement of the axis of the plunger in the barrel. This non-axial alignment between the plunger and the barrel allows for the manufacture of disposable syringes of much lower volume than are already used.

In US Pat. No. 4,386,606, a sharp edge is used on the plunger, cam or barrel to securely lock a syringe with an X-shaped plunger.

US Pat. No. 4,367,738 describes a non-reusable syringe using a plurality of rigid, flexible spikes.

US Pat. No. 4,731,068 shows a firmly fixed spider-like protrusion installed on a cylindrical plunger to seal the syringe after delivery to prevent reuse.

In US Pat. No. 4,952,206, a protrusion is used to position the washer in the valve to prevent flow after drug delivery.

In US Pat. No. 4,961,728, projections that are not parallel to the locking element of the X-type plunger are used.

In US Pat. No. 4,979,943, a reversible stop member is provided that allows operation of the plunger in only one direction.

In US Pat. No. 5,000,737, a round or grooved protruding lock is used that engages an X-shaped plunger.

In US Pat. No. 5,021,047 and US Pat. No. 5,138,466 use locking projections that completely surround the plunger. The operation of the locking device relative to the plunger makes it possible to bend it in a powerful axial mode relative to the ratchet teeth.

In US Pat. No. 5,205,825, a clip that can be inserted to lock an X-shaped plunger is used.

International Publication No. 89/00432 uses a ratchet plunger and a ratchet wall to prevent reuse.

US Pat. No. 5,000,737 relates to a disposable syringe. The figure shows an apparatus adapted to be placed on an X-shaped conventional plunger shaft. The outward points of the longitudinal grooves of this document are adapted to be inserted into the inner cylindrical sidewall or surface of the barrel to prevent movement of the disk relative to the barrel when the plunger axis is moved in the proximal direction (the direction for drawing the drug into the barrel). Since the inward edges are adapted to engage adjacent walls of the X-shaped plunger, the device transitions with the plunger when the plunger is moved to the end (to deliver the drug). 8-16 of the patent relate to the invention claimed in the '737 patent. The device is adapted to be held within a quadrant of the syringe barrel limited by the X-shaped plunger member. According to the patent, it is described as being "extended", ie its length is larger than its width dimension.

On the other hand, the spring locking clip of the present invention is not elongated as described in more detail below. It is compressed into a small sized syringe and easily prepared. It is believed that this syringe is much simpler to manufacture. In the case of axial misalignment, it will not fail, and in fact operates efficiently by axial misalignment. By being constructed and operated in this way, the volume of the syringe can be made much smaller than what can be constructed with prior art syringes. Moreover, the present invention contemplates use with new plungers. The existing spring locking clip is not accommodated in the quadrant of the barrel, which is limited by the X-shaped plunger, but rather extends only partially around the new basically cylindrical plunger located in the barrel. This provides a more uniform pressure of the locking mechanism against the inner sidewall of the barrel and makes the present invention useful for preventing reuse of the syringe used once. The manner of operation, ie the plunger which is pushed out of axial alignment or off center with respect to the axis of the syringe barrel, has a wide range of advantages over the prior art. The '737 patent shows a disk-like member that operates in a manner very similar to the longitudinal grooves claimed in this' 737 patent. It is also intended for use with conventional X-shaped plungers. It also appears difficult to shrink to produce 0.1 cc syringes.

U. S. Patent No. 5,151, 088 relates to a safe injection needle and syringe assembly. Disposable syringe and injection needle assemblies are shown and described as having a small, firm and retractable needle shield provided in a syringe. After injection, the injection needle shield extends to a locked position covering the injection needle. The shield only takes a locked position when the user presses the syringe plunger past the zero volume point. Thus, if the user does not do so accidentally or intentionally, such a device will not be able to prevent reuse. It is an object of the present invention to automatically prevent the reuse of syringes after inhalation, in order to exclude infections between individuals and consequently to exclude needle reuse. Automatic engagement of the locking mechanism is not achieved by the device of the '088 patent. Using the invention of the '088 patent, a user who wants to invalidate the instrument to reuse the syringe can intentionally fail to press the syringe plunger past the zero volume point, thereby avoiding binding of the locking mechanism.

U. S. Patent No. 5,205, 825 to Allison et al. Relates to an insertion element for preventing reuse of plastic syringes. Similar to that shown in the '737 patent by Free et al., Such a device is a locking mechanism intended to be retrofitted into an existing conventional syringe by inserting the device onto a standard X-shaped plunger in a plastic cylindrical barrel of the syringe. To provide. The same devices already manufactured in connection with the devices of the patent of Free et al., Which cannot be made effectively and efficiently with a smaller maximum dosage size, also provide the advantages achieved by the present invention, namely the axis and plunger of the cylindrical barrel. The inability to achieve the result of misalignment is the same as in Allison et al.

U.S. Patent 5,067,942 relates to a disposable hypodermic needle. When the injection needle assembly and syringe are assembled, two separable tabs held in the basket exert a force on the sheath to deflate and expose the ports in the needle, so that fluid can flow through the needle. Upon separation of the needle and syringe, the tab is removed from the basket and effectively broken for further use in pulling the sheath. The present invention is believed to be simpler, cheaper to manufacture, more automated, and more readily employed with smaller size syringes than those shown in the '942 patent.

Many safe syringe designs have also been proposed incorporating an injection needle cover. US Pat. Nos. 4,909,791 and 4,982,842 use jaw members rotatably mounted on a syringe barrel to cover the needle after use.

U.S. Patent No. 4,969,877 discloses a syringe assembly in which an outer casing is provided around an inner chamber or syringe portion, the inner chamber or syringe portion being the outer casing in an operating position and a retracted position at the front and rear ends of the outer casing. Slide on the floor.

U.S. Patent No. 4,013,073 discloses a collapsible disposable syringe when the collapsible walls are constructed such that when the walls are compressed together to release the drug, the walls work together to make the device unusable.

U. S. Patent No. 4,022, 206 shows a method and apparatus for storing and delivering a vaccine to a device previously containing a single dosage. There is no provision for units that cannot be mechanically operated for subsequent use.

US Pat. No. 4,391,273 shows a rigid shaped syringe that includes a pin attached to a piston that penetrates the base wall of the cylinder after injection is complete. This also renders the syringe inoperable after first use. In another embodiment, this patent shows a blade that allows movement of the cylinder in the forward direction, but the blade acts to cut the side wall of the cylinder when trying to recycle the piston or reuse the syringe.

Prior art for preventing reuse of a syringe includes various arrangements for first loading and then locking the plunger of the syringe after being reciprocated to the distal end of the transition to inject the contents of the syringe. For example, US Pat. No. 4,731,068 discloses a two-part locking structure that is assembled at the end of an injection of a syringe and has a band or sleeve dimensioned to be frictionally sliding along the inner wall of the syringe. The spider-like element is installed in a fixed position on the plunger and has protrusion points engaged with the sleeve. If the plunger is first withdrawn, the spider element and sleeve move with the plunger towards the end of the syringe. When the plunger is depressurized towards the injection end, the sleeve is held at the distal end (through functional engagement with the inner wall) with the spider element transitioning towards the injection end with the plunger. When a second attempt is made to withdraw the plunger, the projection of the spider element currently exposed to the inner wall in the absence of the sleeve is bound to the inner wall of the syringe to prevent the second withdrawal.

Another embodiment, shown in the '068 patent, has a sleeve slidably supported on a plunger and engaged with a spider element. The device has a curved spring shaped prong assembled at the distal end of the syringe. On the first withdrawal, the sleeve remains engaged with the spider element, and upon the first decompression, the sleeve moves towards the injection end to expose the tip of the spider element. In an attempt to withdraw the plunger, the second is prevented by binding the plunger and the tip. Other devices, such as US Pat. Nos. 4,781,684, 4,493,703, 4,391,272 and 4,367,738, provide modifications to the plunger or syringe wall structure. They make it impossible to lock or use the plunger after only one direction of movement or initial decompression of the plunger. These also relate to disposable syringes

U. S. Patent No. 5,290, 235 relates to a syringe that is not reusable. In use, the locking member allows the first suction stroke and delivery stroke of the plunger but interacts with the inner surface of the hollow body of the syringe and the guide arrangement of the plunger to prevent the second suction stroke.

The device shown in the '235 patent generally comprises a conventional syringe having a hollow body; An elongated plunger rod extending out of the body for easy movement of the piston, the plunger rod carrying a locking member such as a plate having at least one snag protrusion projecting towards the inner surface of the barrel; And a guide means, the guide causing a relative pivotal movement of the locking member from a first position to a second position in which the plunger freely moves in the distal direction, the protrusions being coupled to the inner wall of the barrel.

The structure of the apparatus of the '235 patent is much more complicated than that of the present invention. The present invention contemplates the use of a ratchet plunger shaft which is basically simply shaped into a cylinder, but with a spring clip installed thereon. The original position of the spring clip will determine the maximum volume of liquid supplied. In contrast, the device of the '235 patent shows a complex plunger. This is not suitable for mass production. The present invention allows a single plunger rod to be used for a variety of maximum dosage syringes. In the '235 patent, each syringe with a different maximum desired dose requires a different distance on the plunger between the first opposing face 22 and the stationary opposing face 26.

The present invention is extremely easy to manufacture, manufacture and assemble. Syringe barrels of standard size are readily available and can also be fully scaled down for use in conjunction with commercially important syringes having a maximum dosage capacity as low as 0.1 cc. The present invention provides a double safety device, ie substantially automatic operation, and in a preferred embodiment, by providing multiple locking mechanisms, as will be described in more detail later, so that reuse of the syringe once used cannot occur. do. The present invention allows for the selective axial position of the spring locking clip on the cylindrical plunger shaft, so that the maximum dosage can be provided by the manufacturer through the spring barrel, and the plunger can be manufactured in a single size. Thus, at the time of manufacture, the location of the spring lock mechanism associated with the barrel and plunger can prevent the physician, nurse, specialist or user from overdosing the particular drug. Since the spring lock clip mechanism can assume several initial positions at the time of manufacture depending on the position of the plunger, it can be manufactured economically since only one cylindrical barrel and plunger element need to be manufactured. The original position of the spring lock clip or instrument relative to the plunger determines the maximum dosage that a particular syringe can administer. Thus, the present invention not only provides a mechanism to ensure that the syringe cannot be reused, but also the spring lock clip mechanism limits the amount of drug that can be administered for any particular use of such a syringe.

As will be described in more detail below, the present invention provides an auxiliary safety mechanism to further disable the syringe after its first use. Rather than being automated, however, this feature requires the user to physically separate the thumb contact disk portion of the plunger from the plunger shaft so that the syringe cannot be used again mechanically. Since the disc, the remainder of the syringe, can be used to facilitate inventory control after the body is discarded, the removed thumb contact disc portion is used as a secondary purpose for inventory control.

Another object of the present invention is to provide another locking feature that prevents the syringe from being used again. In this embodiment, sufficient distal reciprocating motion of the plunger relative to the syringe barrel binds the annular male dove-tail of the thumb contact disk and the annular female dovetail of the cylindrical barrel. mechanically locked in an array like dove-tail). This locks the disc and the shaft completely inside the barrel and prevents the shaft from moving outward relative to the barrel. The prevention of this movement prevents the additional drug from being injected into the body of the syringe so that the device cannot be reused.

The geometry of the present invention allows the device to be manufactured in maximum dosages as low as 0.1 cc. This is due to the fact that the locking device works radially, as described below, ie pushes the plunger rod out of the shaft in the barrel. In this manner of operation, the locking clip needs to be of a constant thickness. There is no need to surround the plunger rod. In construction and operation, the plunger rod, barrel and locking clip are sized to deliver as little drug as a maximum barrel dosage of 0.1 cc and can be reduced without loss of functionality. This cannot be used in the prior art.

DETAILED DESCRIPTION OF THE INVENTION The present invention is a single use disposable application filed Feb. 14, 1994, entitled Single-Use Syringe Assembly, and the name of the invention includes a spring clip lock and a plunger. Partial continuation of US patent application Ser. No. 08 / 232,749, filed April 25, 1994, Single-Use Syringe Assembly Comprising Spring Clip Lock and Plunger. These two applications are incorporated herein by reference.

1 is a side perspective view of a syringe portion of the present invention showing a spring lock device suspended from a ratchet plunger shaft in its initial position, marketed by a manufacturer, initially filling a drug and then subsequent delivery of the drug The syringe of the present invention is shown in a structure adapted to be delivered to a user for the sake of clarity, and the injection needle extending from the syringe is a conventional structure.

2 is a side perspective view of the present invention in a dispensing ready position after drug is filled;

3 is a perspective view of the present invention after drug delivery, showing a spring locking clip in the maximum forward or distal position, performed by one of the rattling teeth of the plunger.

4 is a perspective view showing the manner in which the plunger is cut as a result of the proximity movement of the plunger attempted in the second order;

5 is a perspective view of an embodiment of the plunger shown without a piston element.

5A is a perspective view of an elastic piston element of the plunger mechanism.

6 is a side view of a second embodiment of a plunger in the form of two reduced area gaps between ratchet teeth;

7 is a side view of a third embodiment of a plunger having an enlarged cross-sectional area and a single reduced area gap to prevent tampering.

8 is a side view of a fourth embodiment of the plunger, with three reduced areas, one immediately adjacent the thumb contact disc portion;

9 is a plan view of a flat spring locking clip before being formed into a three dimensional curved shape for use in placement and use in a barrel of a syringe;

10 is a perspective view of the spring lock clip after being shaped.

FIG. 11 is a cross sectional view taken along line 11-11 of FIG. 3; FIG.

12 is a side cross-sectional view of an alternative embodiment of the barrel, plunger and thumb gripping disc portion of the plunger.

FIG. 13 is a pattern with beaded ratchet teeth on the plunger rod, with an intake gap between the ratchet teeth, and a disposable syringe shown in an inhalation state up to the initial stage, that is, until inhalation of the drug to be delivered. Top view of a preferred embodiment of the invention.

FIG. 14 is a plan view similar to that shown in FIG. 13 with the plunger partially drawn out, ie moved in a proximal direction during the withdrawal of the drug following the first intake;

FIG. 15 shows FIGS. 13 and 14 with the spring locking clip disposed over the surface of the beaded rattling tooth until the plunger is fully pulled out, that is, the protruding protrusion of the spring locking clip is pressed against the inner wall of the barrel. A plan view similar to that shown, which prevents the locking clip and plunger from being further drawn out; Drug is completely injected into the barrel during this step; The device is in a state where it is easy to deliver the drug.

FIG. 16 is a plan view similar to that shown in FIGS. 13 to 15, showing that the plunger is in a fully protruding position, ie, fully distal after delivery of the drug, wherein the spring locking clip engages the plunger by cooperating with the base of the ratchet tooth; Moving along the distal end, wherein further plunger withdrawal is prevented by embedding of the projection of the spring clip against the side wall of the barrel.

FIG. 17 is a plan view similar to that shown in FIGS. 13-16 after the second attempted contraction of the plunger has been performed, ie, after the plunger has moved fully to the end to deliver the fully loaded drug for the first time, the plunger is a plunger It is shown that it is separated by the pullout force of the plunger which is greater than the tensile strength of and the pullout force cannot overcome the force of the spring locking clip embedded in the barrel sidewall, and the plunger rod is ruptured at the fracture surface. The figure which shows.

18 shows that the plunger has a beaded rattling tooth, in order to provide intake between the two drug injection strokes of the syringe, i.e. two partial doses, each dose preceded by an intake cycle, can be supplied by the syringe. A plan view similar to that shown in FIG. 13, showing another embodiment of the invention where two intake gaps are positioned between the ratchet teeth so that the syringe is in its initial state, ie before the first intake cycle and the plunger is partially The figure which shows what is in the state before drawing out.

FIG. 19 is a plan view similar to that shown in FIG. 18, with the plunger partially drawn out to intake the barrel prior to filling the barrel with drug for delivery; FIG.

FIG. 20 is a plan view similar to that shown in FIGS. 18 and 19 with the plunger pulled out so that the spring locking clip is disposed over the surface of the first beaded rattling tooth, in which the drug is injected into the barrel and The first dose is easily delivered.

FIG. 21 is a top view similar to that shown in FIGS. 18-20 with the plunger fully pushed to the end first to deliver all drug injected into the barrel, with the plunger rod moving as the spring locking clip moves as the plunger moves A state showing the state moved to the intermediate point along, the second intake and the drug delivery ready state of the syringe.

FIG. 22 is a plan view similar to that shown in FIG. 19 showing a second pulled out plunger rod for loading and inhaling a second dose of drug into the barrel, wherein further withdrawal of the plunger latches the spring locking clip Place it on top.

FIG. 23 is a plan view similar to that shown in FIGS. 18-22, illustrating the plunger rod being moved to the distal position to deliver the drug, wherein the spring locking clip moves with the plunger rod;

FIG. 24 is a plan view similar to that shown in FIGS. 18-23 showing the plunger rod delivering all the drug and moving the spring lock clip to the final distal position by fully moving to the distal position;

FIG. 25 is a plan view similar to that shown in FIGS. 18-24, showing a ruptured plunger rod as a result of further attempted withdrawal of the plunger, wherein the attempted withdrawal exceeds the structural strength of the plunger rod, thereby Resulting in a rupture at and the embedding strength of the spring locking clip exceeds the tensile strength of the plunger rod.

26-33 illustrate alternative embodiments of the plunger rod, varying the number and position of the ratchet teeth and the position and length of the intake gap.

The present invention relates to a disposable syringe in which reuse is mechanically prevented. It is an object of the present invention to provide a disposable syringe which is simple in structure, inexpensive to manufacture and which automatically prevents reuse. Another object of the present invention is to provide an inexpensive syringe which can mechanically prevent reuse and can be produced with very low dosage doses. For example, it is a particular object of the present invention to provide a disposable syringe capable of a maximum dosage as low as 0.1 cc.

It is another object of the present invention to provide a disposable syringe with less plunger in power and smoother mechanical operation than commercial maximum standards.

Another object of the present invention is to provide a disposable syringe which can be selectively and repeatedly inhaled before the drug is injected into the barrel.

It is a further object of the present invention to provide an inexpensive spring-like instrument that, when placed on a ratchet plunger shaft, limits the amount of drug that can be injected and administered into the barrel of a syringe. The initial position of the spring lock mechanism relative to the cylindrical ratchet axis determines the maximum dose of a particular syringe. It is therefore a particular object of the present invention to provide a disposable syringe which can have several maximum dosage capacities depending on the initial axial position of the spring locking clip with respect to the plunger axis. Thus, barrel production of a single size provides economic production.

Another object of the present invention is to ensure that a disposable syringe is provided that cannot be intentionally easily disabled. It is also an object of the present invention to ensure a disposable syringe adapted to operate by radial displacement between the plunger and the barrel axis of the syringe. This is achieved in part by using a new plunger shaft that is basically rod-shaped, not X-shaped, and by using a spring-type locking clip that can be positioned on the plunger shaft and that contracts radially in and out. The non-axial alignment between the cylindrical plunger shaft and the inner barrel wall of the syringe can reduce the disposable locking mechanism of the syringe, which can provide a dosage as low as 0.1 cc. It is a particular object of the present invention to provide a disposable locking mechanism for a disposable syringe that can be used on a cylindrical plunger shaft. By removing the X-shaped plunger, the present invention can be more easily manufactured with smaller dimensions. By using the ratchet plunger rod and the spring locking clip of the present invention, the essential part shown in the prior art of the locking clip substantially surrounding the cylindrical plunger axis is removed. In this way, very small volumes of syringes can be made.

The plunger shaft of the present invention further comprises a plurality of beaded latch teeth in a more preferred embodiment. As will be described later, the spring locking clip is initially positioned on the selected one tooth or bead of the plunger. Therefore, according to the present invention, more precise dosage limiting is possible than can be used with the prior art apparatus. While mechanical locking between the spring locking clip and the plunger ensures that the maximum dose is administered in a fixed full dose, the prior art adjusts the maximum dose by means of a highly variable sliding position of long grooves along the X-shaped legs of the plunger. Precise adjustment is never easy.

Another object of the present invention is to provide a thumb contact disc portion of the plunger shaft which can be selectively bent, twisted or removed from the plunger shaft after the syringe has been used. In this way, the thumb contact disc portion can be used to track syringe usage and inventory. Moreover, removing the thumb contact disk portion of the plunger shaft serves to make the syringe unusable further and to easily prevent reuse.

It is another object of the present invention to provide another locking mechanism for preventing further use of the syringe from reuse after intended use for single use. This locking mechanism is achieved by the cooperation of the annular male dovetail receptacle portion at the adjacent end of the barrel of the syringe with the annular male dovetail portion of the thumb contact disk portion of the plunger shaft. The complete reciprocating cycle of the plunger shaft relative to the cylindrical barrel of the syringe acts to mechanically lock the plunger shaft to its maximum distal position thereby preventing the second withdrawal of the plunger shaft to the barrel of the syringe.

Another object of the present invention is to provide a mechanism in which syringes of the same dimensions can be regulated to contain and deliver different doses, thus reducing the need for syringes of different sizes.

The present invention relates to a mechanical means using a ratchet plunger and a spring locking clip to achieve many desirable features, as described above. Operation of the syringe assembly relies on a loosely bound spring-locking clip that draws in the syringe and fills the drug as needed when the plunger is withdrawn. These clips are nearly semi-cylindrical, have the ability to bend radially inwards and outwards, and include outwardly facing projections to allow them to be positioned sufficiently independently to identify variations in barrel diameter due to manufacturing tolerances or defects. . The invention also includes an alignment element which acts as a locking clip advancing towards the needle. Alignment elements add stability when the plunger is attempted to be reused for a second refill as described below. The plunger includes a front seal after the first drug delivery to provide a smooth function by applying a uniformly distributed force against the nested protrusion during the arbitrarily attempted secondary withdrawal of the plunger.

According to a preferred embodiment of the present invention, a gap is provided between adjacent ratchet teeth. Subsequently, after intake, the plunger is withdrawn to fill the syringe, and the spring locking clip secured in the syringe barrel is pressed against the cam over one or more teeth of the cylindrical rattling plunger as a result of the radial bending. Since the clip is radially open, it can accommodate a variable diameter of each tooth of the nearly semi-cylindrical plunger. During the delivery of the fluid by the relative forward movement of the plunger and the piston, the clip is bent radially. This clip is forwarded or pressed relative to the barrel by the plunger. After injection, when the plunger is in the foremost position, the clip prevents any second reverse withdrawal of the plunger because the protrusion is embedded inside the plastic barrel wall. Any attempt to overcome the friction produced is because the decrease in tensile strength due to the reduction in the cross-sectional area of the plunger at the given position is less than the force required to overcome the frictional resistance provided by the projections embedded in the inner wall of the barrel. Causes destruction. In another embodiment, two or more reduced diameter portions of the plunger may be provided to further prevent reuse.

In another embodiment, a single plunger rod may be provided with multiple gaps between adjacent ratchet teeth. This allows the syringe to be used with a constant number of times depending on the optional inspiration.

It is an object of the present invention to provide a design which can be easily manufactured by standard molding and assembly methodologies at a unit cost comparable to the price experienced to date in the manufacture of disposable plastic syringes.

It is an object of the present invention to achieve smooth operation of the syringe. Beaded ratchet teeth provide in-output and smooth operation of the plunger from less than the maximum required by industry standards. It is an object of the present invention to provide a disposable syringe which does not fail, especially with a small volume syringe size.

It is a further object of the present invention to provide a plunger and a spring locking clip which allow positioning and actuation of the locking function as a result of radial bending of the locking member around the plunger and in the barrel of the syringe.

It is another object of the present invention to provide a spring locking clip having a flexible, locking or contact point that can interact with the barrel wall independently and allow for a change in barrel diameter.

It is another object of the present invention to provide a syringe which makes it impossible to operate the syringe even when attempting to reuse it.

It is a further object of the present invention to provide a supplementary failsafe device, i.e. a means for providing tamper resistance.

It is a further object of the present invention to provide a design which imparts the above-mentioned features to a syringe capable of accurately delivering as little as 0.1 cc of liquid.

It is an object of the present invention to provide these features in a single syringe having a variable predetermined maximum fluid volume that can be injected into the syringe.

It is an object of the present invention to achieve the above-mentioned desirable objects by using materials approved by official government regulations.

It is an object of the present invention to be able to modify the syringe to minimize accidental needle punctures.

It is an object of the invention to provide a disposable syringe which can be inhaled one or more times with the same or different inspiratory amounts before filling the drug.

It is also an object of the present invention to provide a multiple locking mechanism that renders the syringe unusable in a variety of ways and prevents access to the locking mechanism in operation.

It is an object of the present invention to allow variable fluid amounts and selected multiple uses to be delivered according to a given barrel diameter.

The objects, features and advantages of the present invention will become more apparent from the following detailed description of the preferred embodiments of the present invention considered with reference to the following drawings.

As shown in the figure, the syringe 10 of the present invention includes a cylindrical main cylinder body 12 and a reciprocating plunger member 14 slidably received and contained within the cylinder body 12. Suitable materials for the cylinder body are insoluble, FDA-approved clear medical polypropylene that does not react with most drugs. Preferred plunger materials are medical polypropylene modified by incorporating suitable additives to provide brittleness to the resin.

Injection needle 15 is attached to the distal end of syringe 10 in a conventional manner. Of course, the syringe can be sold separately from the injection needle. A detailed description of the structure of the needle and the manner in which the needle is attached to the syringe is not required for a full understanding and recognition of the present invention. The needle 15 is fixed to the tip 18 of the cylinder body 12. For the purpose of this description, the end of the cylinder body 12 facing the tip and the needle is referred to as the distal end, and the direction or movement towards that end is referred to as the distal direction. The other end of the syringe, ie the end of the plunger member 14 with the thumb contact disk 20 and the finger handle 26, is referred to as the proximal end, and the direction or movement towards that end is referred to as the proximal direction. As can be seen in the figure, the thumb contact disk 20 is fixed to the proximal end of the plunger member 14 and not only facilitates the withdrawal or proximate movement of the plunger member 14 relative to the cylinder body 12. Promote dosing delivery or distal movement of the plunger member 14 towards the tip 18 of the cylinder body 12. Proximity movement inhales the syringe and then inhales the drug through the needle into the barrel or chamber of the syringe, while distal movement delivers the drug retained in the barrel through the tip 18 and the needle 15. The drug is delivered from the cylinder body or barrel by the sliding action of the elastic piston 44 relative to the inner sidewall 17 of the barrel.

The thumb contact disk 20 is secured to the segment 22 of the plunger member 14. In the embodiment of the invention shown in FIG. 8, the segment 22 is partially truncated-conical and exhibits a fracture diameter 24 of reduced diameter. As shown in FIG. 8, the reduced diameter end of the segment 22 forms the base for the thumb contact disk 20. After using the syringe, the thumb contact disk 20 can be bent against the fracture surface 24 until the disk is broken or detached. Removal of the thumb contact disk 20 makes it difficult to reuse the syringe after use. This removal of the disk 20 not only makes the syringe unusable further, but also acts as a convenient and compact inventory management mechanism.

1 to 4, the cylinder body 12 has a finger grip or finger support plane 26 at its proximal end. This provides a finger support surface that is convenient for relatively reciprocating the plunger member 14 relative to the cylinder body 12 and provides a pedestal surface for the user's fingers during use.

The plunger member 14 is a rod having a basic structure. The truncated-conical ratchet tooth 28 extends over some length of the plunger member 14. As shown in the figure, each ratchet tooth 30 includes a cam surface or inclined surface 31 which is inclined outwardly extending (from the proximal end to the distal end) and has an enlarged diameter D1. ) Are formed into adjacent ratchet teeth by a base or common plane 32 having a (relative to upper relative tooth) and a reduced diameter D2 (relative to lower relative tooth).

In the embodiment of the invention shown in FIGS. 13 to 32, the straightly sloped surface 31 is replaced by a convex surface. In this manner, the outer surface of the ratchet tooth is a beaded surface and provides a smooth surface (during the proximity plunger movement) with the camming of the spring locking clip and the distal movement of the plunger. Beaded rattling teeth are each provided with a large diameter in the middle between the teeth. This is equal to the diameter D1 of the truncated-conical ratchet tooth of FIG. 1. The bead shape of the ratchet tooth provides a smoother operation during plunger withdrawal. It has also been found that the plunger in power is greatly reduced and almost the same as when the spring lock clip is not used.

In the embodiment shown in FIG. 7, the plunger seal 34 surrounds the plunger member 14 just above the closest rattling teeth. The plunger seal 34 may be integrally molded or formed with the plunger, or alternatively may be made of a separate elastic element. The interference fit of the plunger seal 34 (or segment 22 of the plunger shown in FIG. 1) to the barrel restricts access to the spring locking clip and renders the device improperly tampered. The tight tolerances of the parts between the inner sidewall 17 of the barrel and the seal 34 (and / or segment 22) are indicated by small gaps 41. The plunger seal 34 or segment 22 has an outer diameter greater than the diameter D1 of the ratchet teeth, and in the embodiment of FIG. 7, the plunger seal 34 is only slightly smaller than the diameter of the inner side 17 of the barrel. Has a small diameter. The plunger seal provides a barrier between the outside of the syringe and the rattling tooth, thereby preventing foreign matter from being introduced between the inner sidewall 17 of the cylinder body 12 and the plunger seal 34. Thus, the plunger seal 34 or segment 22 functions as a sealing device for preventing unauthorized access to the spring lock clip 40 and thus cannot be intentionally disabled. In another embodiment, the plunger seal 34 is rubber and in physical contact, and at least in part is compressed by the relative diameter of the inner sidewall 17.

The distal end of the plunger member 14 includes a piston or fluid-propelled sealing member 44. It is preferably made of a rubber material which is a partially compressible material. Preferably, the piston is a medically approved synthetic rubber. Here, the piston 44 may be integrally molded or formed with the plunger or may be a separate rubber member. As shown in Figs. 5, 5A and 6-8, the piston can be attached to the distal end of the plunger by a blind hole forcibly installed on the truncated-conical projection shown in Fig. 7. This secures the rubber piston to the plunger. The piston 44, when radially compressed by the inner sidewall 17 of the barrel, has a diameter substantially the same as the diameter of the inner sidewall 17 and provides a sealing contact sliding between the piston and the inner sidewall. to provide. When the plunger member 14 reciprocates within the cylinder body 12, all fluid (end of the piston 44) is extruded past the needle 15 through the tip 18. Sealing member 44 prevents any drug or fluid from entering the upper cavity (or proximal end). Of course, the piston 44 moves together with the plunger member 14 and is physically fixed to the plunger member.

At the end proximal to the piston 44, like the plunger seal 34 or segment 22, a secure seal is provided to prevent unauthorized access to the ratchet teeth 28 and the spring locking clip 40. An enlarged plunger portion seal section 52 is adjacent. It also prevents paper clips, knife points and the like from approaching the adjacent space of the piston. The diameter of the section 52 is approximately equal to the diameter of the inner sidewall of the cylinder body 12.

The locking spring 40 is clearly shown in FIGS. 9, 10 and 11. In a preferred embodiment, when shaped, the basic structure is a hollow six-sided structure with one side open. The overall shape may be semi-cylindrical and extend around the plunger by about 200 °. Preferably, the spring is formed from a thin piece of elastic metal, preferably a single sheet and thickness of stainless steel. This material can be deployed separately (by the manufacturer) for initial placement around the particular ratchet tooth 30 selected, and after being placed on the plunger member, the locking spring 40 has its original dimensions and structure. It must be elastic to restore to The elasticity allows the spring locking clip 40 to be secured around the plunger member to bend radially inward and outward after being received inside the barrel. The locking clip is installed on the plunger rod by pressing the open end above the ratchet teeth, so that the front walls 70 and 72 are temporarily deployed. After initial placement, the spring member cannot be separated from the plunger due to the dimensions of the open end of the locking clip relative to the diameter D1 of the ratchet teeth (frust-conical or beaded) of the plunger.

In another form, due to the limited space between the inner sidewall 17 and the plunger occupied by the locking clip 40, the locking clip is secured around the plunger even when extending below 180 ° around the plunger. The dimension of the spring locking clip 40 is such that the distance between the edges of the front walls 70 and 72 is smaller than the diameter D1 of the ratchet tooth. In one embodiment, it will be appreciated that the locking clip 40 extends at least 180 ° around the plunger member 14 such that after placement, the plunger member cannot be accidentally released. In fact, in a preferred embodiment, the locking clip extends about 200 °. As in the preferred embodiment, when the syringe is configured to provide 0.1 cc of drug, the locking clip can be much smaller around the circumference. It was determined that it should extend at least about 27 ° around the plunger.

In a preferred embodiment of the invention, the height when the spring locking clip 40 is formed is less than the total width W. In this way, the locking clip is disc shaped and does not extend. Therefore, it requires less material and can be manufactured with a high speed manufacturing apparatus, which is easier and cheaper than the stretching apparatus. The figure illustrates a locking clip extending over about two ratchet teeth (see FIGS. 1 and 2) for ease of illustration only. In actual production, however, the height of the spring locking clip is made lower.

The locking clip has a flat rear section 60 and a pair of opposing outwardly extending side walls 62 and 64 fixed to the side edges of the rear section. Extending inward from the outermost edges 66 and 68 of the side walls 62 and 64, respectively, are the front walls 70 and 72. Each rear section 60 and side walls 62 and 64 are rectangular in structure. The front walls 70 and 72 have angled edges 71 and 73, respectively (see FIG. 9). The leading vertical edges 74 and 76 of the front walls 70 and 72 are separated by less distance than the diameter D1 of the base 32 of the ratchet teeth 28 as described above. In this way, as described above, during manufacture of the syringe, the spring locking clip 40 can extend outwards and around the selected ratchet teeth 30, with the leading vertical edges 74 and 76 being plunger. As it passes over the diameter D1 of the base 32 of the tooth of the teeth, the elasticity of the locking clip forces the locking clip to take back its original size. In this way, the spring lock clip is not accidentally released or removed from the plunger member unless a physical force is intentionally applied. As noted above, in another embodiment of the invention where the locking clip extends to about 27 ° for a 1 cc size syringe capable of delivering a dosage as low as 0.1 cc, the locking clip is Since the inner space of the barrel is large enough to be occupied by the plunger and the clip, it cannot be removed from the plunger after being inserted into the barrel. Thus, the locking clip cannot be released from the plunger. Rather, it is interposed between the plunger and the inner sidewall 17 of the barrel.

Top edge 78 extends along rear section 60. Basically it is the tab 80 extending upward from the top edge 78 at the center of the rear section 60. This tab 80 has an edge 82 configured to be able to contact the outer edge of the base 32 of the ratchet tooth. The tab 80 is coplanar with the rear section 60. The tabs contacting the edges of the teeth of the plunger prevent rocking motion of the clip relative to the plunger during plunger movement and ensure alignment between the clip and the plunger. The tap prevents jamming and promotes stabilization.

Camming teeth 83 and 85 oriented inward in the proximal direction extend upward from front walls 70 and 72, respectively. The locking clip 40 hangs on a selected latched tooth (frust-conical or beaded) when placed on the plunger. The inwardly angled camching teeth move the clip distally during the delivery stroke. More specifically, the teeth are in contact with the base 32 of the ratchet teeth on which the clips are suspended. The clip is pushed to the end as the plunger moves to the end. Gaps 91 and 93 (see FIG. 9) are flexible adjustment gaps that adjust the flexibility of the camming teeth. Edges 87 and 89 are initially located on a smooth beaded wall or on the inclined surface 31 of the ratchet teeth in embodiments where the ratchet teeth are beaded. The upper edges 87 and 89 come under the base of the ratchet teeth upon distal movement of the plunger, so that distal movement of the plunger carries the clip with the plunger. However, as the plunger moves in the proximal direction, when the spring locking clip is held in place inside the barrel by the action of the locking teeth 84, 86, 88 and 90 embedded in the inner sidewall 17 of the barrel. The elasticity of the teeth 83 and 85 causes the teeth to be positioned on the inclined surface 31 or convex surface of the ratchet teeth of the plunger through the radial bending of the clip.

The movement of the plunger 14 in the distal direction is such that the locking spring can move with the plunger because the base 32 of the ratchet tooth is pushed onto the top edges 87 and 89 of the camming teeth 83 and 85. Exerting strength. However, the resiliency of the locking clip 40 causes the plunger to be in close proximity to the held-in-position or fixed locking clip 40 because the camming teeth are positioned over the inclined or convex surface 31. To move in the direction of

Extending outwardly and outwardly from the top edges of the sidewalls 62 and 64 are locking teeth 84, 86, 88 and 90. Locking teeth 84 and 86 extend from sidewall 62, and locking teeth 88 and 90 extend from sidewall 64. Localized sections 95 and 97 serve to carry and enhance the action of locking and buried teeth 84, 86, 88 and 90. The flexible control gaps 99 and 101 adjust the flexibility of the sections 95 and 97. The locking teeth are rectangular in structure and terminate at the contacts 105, 107, 109 and 111. The contact extends outward from the outer planes of the side walls 62 and 64, and in fact, the locking point is in contact with the inner side wall 17 of the cylinder body 12. The locking point is supported against the side wall. Since the hardness of the contact is greater than the hardness of the inner sidewall 17 of the cylinder body 12, when the locking clip 40 is about to be moved in the proximal direction by the plunger, the contact is the inner sidewall surface of the cylinder body. Landfill The radially outward elasticity of the spring locking clip embeds the contact in the side wall 17. When this proximity movement is attempted, the contact prevents the locking clip from moving in the proximity direction. However, since the contact is bent radially inward and slides over the inner sidewall 17 during the movement of the plunger in the distal direction, the locking clip can move in the distal direction. The shape and elasticity of the device allows the radial bending described above. The distance between the contacts 105, 107, 109 and 111 may be smaller than the inner sidewall diameter of the cylinder body 12, but because the contacts extend outward with respect to the outer plane of the sidewalls 62 and 64, all The contacts 105, 107, 109 and 111 are in contact with the inner sidewall 17 of the cylinder body 12. By using multiple contacts, the embedding of the locking clip is ensured even if there is a non-uniformity of tolerance for the inner sidewall 17 of the barrel.

Semicircular tab 110 extends distal from rear section 60. The semi-circular tab is balanced with the tab 80 and further prevents jamming of the clip when the plunger moves. The semicircular tab is bent radially inward toward the plunger at or around the edge 112. The tab 110 provides smooth end movement of the clip and plunger without scratching the barrel interior. When the plunger moves completely in the distal direction, the tab 110 is actually forced between the plunger seal 52 and the side wall 17 to further secure the clip in the distal position.

The structure, manufacture and use of the device are as follows. The cylinder body 12 is formed of the same material in the same manner as is done in connection with a conventional medical syringe. Preferably, the plunger member 14 with ratchet teeth (beaded or truncated-conical) and seals 34 and 52 is formed as a single plastic molded article. In a preferred embodiment, the plunger is formed of plastic with brittle additives. The rubber piston 44 is attached to the plunger. The manufacturer determines the maximum dosage for a particular batch of syringes. Manufacturers choose to reduce the size of the syringe barrel and / or adjust the position of the spring lock clip on the plunger rod to be used for a particular maximum dosage of more standard size syringes. In view of such maximum dosage, the spring locking clip 40 is positioned on the ratchet tooth 30 corresponding to the desired maximum dosage. Each ratchet tooth may be marked with an appropriate identification mark during molding to facilitate positioning of the locking clip 40 around a particular ratchet tooth that is either commercially available or corresponding to a particular maximum dosage.

The placement of the spring clip is achieved by deploying the front walls 70 and 72 which position the vertical edges 74 and 76 above the base 32. Positioning of the locking clip 40 towards the distal end of the plunger member 14 provides a lower maximum dosage to the syringe than in the case of positioning of the same locking clip 40 towards the proximal end. During the placement of the clip, the edges 74 and 76 of the clip are physically developed such that the distance between them is equal to the diameter D1 of the base 32 of the ratchet tooth. This is achieved by the radial elasticity of the spring clip. The clip can slide on the plunger. The clip is not held firmly against the plunger, but rather the camming teeth 83 and 85 contact the inclined or convex surface 31 such that the locking clip is suspended from the ratchet teeth.

When the leading edge passes through the diameter D1 of the ratchet plunger member, the elasticity of the spring lock clip forces the edges 74 and 76 to once again take their original size. In this way, the locking clip 40 is positioned around the plunger member so that the clip can be easily removed once without applying force to re-deploy the edges 74 and 76. Those who can recognize it. The locking clip is held on the plunger by camming teeth 83 and 85 which are larger than 180 ° structures and located on the inclined surface 31 of the ratchet teeth. The locking clip fails to grip the rattling tooth and remains loose on the inclined or convex surface of the tooth. The upper edges 87 and 89 of the teeth 83 and 85 protrude as described above, or are bent inwards a sufficient distance so that they are supported against the inclined or convex surface 31 of the particular ratchet tooth. And contact.

The locking clip 40 is in a proximal direction with respect to the plunger member 14 because relative movement is prevented by the mechanical interaction of the upper edges 87 and 89 of the camming teeth below the base of the ratchet teeth adjacent upwards. Can't move. As the locking clip is placed in the desired position, the manufacturer completes the assembly process by securing the plunger member 14 in the cylinder body or barrel along the locking clip 40. The elasticity of the spring allows the plunger and the clip to be inserted into the barrel. The article is then packaged and delivered to the end user.

In the embodiment of the present invention shown in FIGS. 18-33, the syringe plunger has an intake gap 114 between the disc-shaped thumb element and the ratchet tooth or between two frusto-conical or beaded ratchet teeth. do. The length of the intake gap is determined by the manufacturer. The intake gap 114 allows the plunger to reciprocate, i.e., without moving the locking clip during the distal movement of the plunger, but in the proximal direction and rearward for intake. As long as the clip is positioned on the intake gap, even if the plunger is moved one or more times in the proximal and distal directions, the movement of the locking clip does not occur. The locking clip will only function as a "disposable" when the plunger is pulled out in the proximal direction to the extent that the locking clip is positioned at least above the distal latch tooth. Thus, as shown in FIGS. 15 and 16, the distal movement of the plunger moves the locking clip.

1 to 12, the injection needle 15 is inserted into the vial, and the thumb contact disk 20 moves in a proximal direction with respect to the finger handle 26. During the contraction or close movement of the plunger, the locking clip 40 remains fixed in the barrel as a result of the outward radial bending of the locking spring, thereby embedding the tooth in the side wall. The plunger may move in a proximal direction until the top edge of the seal 52 contacts the bottom edge 112 of the locking clip 40. When such contact occurs, the plunger member (because the contacts 105, 107, 109 and 111 of the locking teeth 84, 86, 88 and 90 are physically embedded in the inner sidewall 17 of the cylinder body 12). No further proximity movement of 14) occurs.

Those skilled in the art will understand that the locking clip 40 cannot move when the plunger member 14 moves in the proximal direction. The contact prevents any near movement of the locking clip. The initial position of the locking clip and thus the locking teeth 84, 86, 88 and 90 relative to the plunger determines the relative maximum reciprocating momentum of the plunger in the barrel and thus the maximum dose that can be administered by the syringe. During movement of the plunger in the proximal direction, the tab 80 and tab 110 of the locking clip slide or are positioned over the edge of the ratchet tooth. The tabs maintain the alignment of the device and at the same time prevent jamming of the device. When the plunger member 14 is withdrawn or moved in a proximal direction with respect to the cylinder body 12, the radial elasticity of the teeth of the spring locking clip 40 is such that the edges 87 and 89 have their respective ratchet teeth 30. Over each of the inclined surfaces or beaded surfaces 31. Since the locking clip is held inside the cylinder body 12 in a relative position by the interaction of the contacts 105, 107, 109 and 111 with respect to the inner cylindrical surface 17 of the cylinder body 12, the plunger member 14 may be fully withdrawn until seal section 52 contacts bottom edge 112 of locking clip 40. However, in this case, further proximity movement of the plunger can only be embedded into the inner sidewall 17 of the cylinder body 12, so that further proximity movement of the plunger member 14 is mechanical. Is prevented. Thus, the plunger member is limited in its relative motion with respect to the cylinder body.

Depending on the drug contained within the cylinder body 12, more particularly between the tab 18 of the cylinder body 12 and the piston 44 (or 109 of FIG. 13), the user may need as many needles as necessary. 15) can easily deliver the drug. The needle is inserted through the patient's skin, and the user moves the plunger member 14 to the distal end by applying pressure onto the thumb contact disk 20, thereby causing the piston 44 to be distal to the distal end. Thus all drugs are delivered through the tip 18 and the needle 15. Since the top edges 87 and 89 of the camming teeth 83 and 85 are pushed to the end by contact with the base 32 of the ratchet teeth, the locking clip 40 causes the plunger member 14 to be drugged. As it moves to the end to deliver, it bends radially inward in the barrel and slides in the end direction. The contact prevents only proximal movement of the locking spring; Distal movement is permitted by the sliding of the contact along the intrinsic elasticity and the inner sidewall of the locking clip.

After all the drug has been delivered from the syringe, the seal 52 over the piston 44 abuts the bottom edge 112 of the locking clip. This is illustrated by the intake embodiment of FIG. 16. Since the locking clip 40 (or 106 in FIGS. 13-16) adjacent the seal 52 is embedded in the side wall 17 when the plunger is about to move again in the proximal direction, the plunger member with respect to the cylinder body 12 The secondary reciprocating motion of 14 is mechanically prevented. Secondary proximity movement is prevented by contacts 105, 107, 109 and 111 embedded in the inner sidewall 17 of the cylinder body 12. Thus, it should be understood that the second reciprocating motion for injecting the drug or medicament into the syringe 10 is mechanically prevented because the plunger member 14 cannot again move in close proximity to the cylinder body 12.

In order to further disable the syringe 10 for subsequent potential use, the user may bend or twist the thumb contact disk 20 along the fracture surface 24 until it ruptures, if necessary. . Without the thumb contact disk 20 fixed to the plunger member 14, even if anyone can disable the spring lock clip mechanism, it is very difficult to reciprocate the plunger member 14 in both directions. Moreover, the thumb contact disk 20 can function as a means for limiting syringe statistics. For example, any number of such disks can be collected and retrieved from the manufacturer or supplier for exchange with the same number of new syringes. Inventory and accounting adjustments are easier to track through the flat disk than rely on bulky syringes.

In another embodiment of the present invention, the thumb contact disk has an inclined thumb section 120 and a second inclined outer wall disk shaped section 122. These include an annular male dovetail arrangement for the plunger. The proximal portion of the cylinder body 12 adjacent the finger handle 26 has an annular inwardly oriented edge 130 that terminates within the locking lip 132. These include an annular female dovetail arrangement for the barrel. Thus, when the thumb contact disk 20 is fully reciprocated in the distal direction, the outer wall section 122 inclined until the locking lip 132 overlaps with the second annular disk-shaped section 122. This slides and thus prevents any further proximal and distal movement of the plunger relative to the cylinder body 12. Thus, although it is permitted by the elasticity of the barrel and the gap at the proximal end, it is allowed to be positioned above the edge 134 until the edge 130 is held by the locking lip 132, at the point of the locking lip 132. It will be apparent and apparent to those skilled in the art that the minimum diameter of the edge 130 is smaller than the maximum diameter of the edge surface 134.

In another embodiment of the present invention, a mechanism for preventing tampering with a locking mechanism is provided. After the first complete distal movement of the plunger, the locking clip is embedded in the sidewall of the syringe adjacent to the seal 52. The distal force required to overcome the force of the locking clip embedded into the side wall of the barrel is such that a second attempted proximity movement along its length, preferably directly above the locking clip (see FIGS. 4 and 17). The tensile strength of the plunger is exceeded to physically separate the plunger. In order to concentrate the cut at such a position, the reduced diameter section of the plunger is positioned above the seal section 52. In a preferred embodiment, the reduced cross-sectional area of the plunger is positioned so that a break occurs directly above the proximal surface of the clip. As can be seen in FIGS. 6, 7 and 8, two or more reduced regions 114 and 116 serve as potential regions to be cut by the movement of the plunger.

As shown in FIG. 11, the radial elasticity and strength of the locking clip actually moves and forces the plunger to deviate from the axial alignment with the axis of the barrel. Thus, even with very small diameter and volume syringes, locking clips can be provided that function to prevent reuse. Between the plunger and the side wall of the barrel only a metal of constant thickness is required across the entire diameter of the barrel. In another embodiment, because the clip does not act symmetrically around the plunger, but rather asymmetrically, the locking clip may be made to extend as small as about 27 ° of the 360 ° plunger. In this way, very small volumes of syringes with anti-reuse mechanisms can be achieved. The directional force of the locking teeth pushes the plunger out of alignment.

FIG. 18 is a plan view similar to FIG. 13 showing another embodiment of the present invention. The truncated-conical ratchet teeth were replaced with beaded ratchet teeth. Two intake gaps 120 and 122 are provided on the plunger, with a single ratchet tooth between them. The gap is constrained on its distal end by ratchet teeth. Since the diameter of the rods in the gap is smaller than the inner diameter of the clip, they can easily reciprocate without moving the clip. Two intake gaps allow inspiration before each two drug intake strokes of the syringe, ie two partial doses may be supplied by the syringe, where each dose is preceded by an intake cycle. 18 shows the initial stage of the syringe, i.e., before the first intake cycle and before the plunger is partially withdrawn.

FIG. 19 is a plan view similar to FIG. 18 showing a state where the plunger is first partially withdrawn upon inspiration and then withdrawn to fill the barrel with drug for delivery. The plunger rod may reciprocate until the user attempts to withdraw the plunger rod in the range in which the locking clip is positioned over the first ratchet teeth 130. During the proximity stroke, the drug must be injected into the barrel. As long as the locking clip is between the ratchet teeth, i.e. on the intake gap, the plunger can be moved one or more times in the proximal and distal directions, once the plunger rod is pulled out in the proximal direction so that the locking clip is latched. When positioned over teeth 130, distal movement of the plunger rod delivers the drug and moves the locking clip distally. FIG. 20 is a plan view similar to FIG. 18 showing the plunger withdrawn so that the first ratchet teeth are positioned above by the locking clip relative to the intake gap 122. In this position, the drug is injected into the barrel. FIG. 21 is a plan view similar to FIG. 18 showing the plunger first pulled completely to the distal end to deliver all drugs injected into the barrel. The spring locking clip is shown to move toward the distal end of the syringe because it moves in the direction in which the plunger moves. As shown in the figure, the spring locking clip is moved to an intermediate position between the distal and proximal end of the syringe.

FIG. 22 is a plan view similar to FIG. 18 showing a second drawn plunger rod for intake before loading the drug into the barrel; FIG. Again, the plunger rod can be moved in the proximal and distal directions without the movement of the spring locking clip, so that the clip does not contact the base of the ratchet teeth on the intake gap 120. FIG. 23 is a top view similar to FIG. 18 showing the plunger rod in the distal position for delivering the drug. The spring locking clip is shown moving with the plunger rod. The reason is that the clip is in contact with the ratchet teeth 132, in particular the ratchet teeth engagement of the clip is located below the base of the ratchet teeth 132, and the distal movement of the rod moves the clip. Because it is. FIG. 24 is a plan view similar to that shown in FIG. 21 showing a state in which the plunger rod has completely moved to its distal position to deliver all drugs and move the spring locking clip to its final distal position. Further withdrawal of the plunger is prevented by embedding the projection of the spring lock clip in the inner barrel wall of the syringe.

FIG. 25 is a plan view similar to that shown in FIG. 17 showing a state in which the plunger rod is broken as a result of further attempts to withdraw the plunger. Since the tried in force exceeds the structural strength of the plunger rod, breakage is caused. The buried force of the spring locking clip exceeds the in-output. The fracture occurs at the fracture surface.

FIG. 26 has two large intake gaps and one small intake gap, with a piston and sealing piston for pushing out the drug, prior to placing the spring locking clip on the rod and before being placed in the syringe barrel; The plunger element is shown. FIG. 27 shows a plunger having a slide tube at its proximal end to facilitate axial sliding of the plunger in the barrel of the syringe. The slide tube prevents foreign matter from entering the barrel. As can be seen from the figure, the lower side of the thumb binding pressure disk is deformed. 28 shows a plunger with two intake gaps. 29 shows a plunger having a beaded latch tooth with a single intake gap. This plunger can be used by manufacturers for large volume ranges of the same barrel depending on where the user initiates drug delivery, ie the position of the clip along the rattling teeth. 30 shows an embodiment of a plunger having three large intake gaps and one small intake gap. Such plungers may be used to deliver four doses of drug, each dose being received by a syringe barrel preceded by an inspiratory movement. FIG. 31 shows the plunger of FIG. 26 after a single dose of drug delivery operation has occurred (two doses), when the user attempts to use the syringe again, the output is broken at the fracture surface beyond the structural strength of the plunger. Indicates. In this case, however, the embedding force of the spring locking clip to the inner wall of the barrel exceeds the strength of the plunger rod. FIG. 32 illustrates the fracture surface or fracture point of the plunger shown in FIG. 25. The plunger may have one or more break points to prevent the syringe from being used repeatedly. The plunger breaks at any break point if the user attempts to withdraw the plunger after the first full use has occurred, since the attempted in-output exceeds the structural strength of the plunger. 33 is another embodiment showing a plunger rod having three ratchet teeth.

Various embodiments of disposable hypodermic needle and syringe assemblies have been described. Although the invention has been described with reference to specific embodiments thereof, the description is intended to illustrate the invention and is not intended to limit the invention. Various modifications and applications can be made by those skilled in the art without departing from the true spirit and scope of the invention.

Claims (19)

A hollow barrel having an inner cylindrical sidewall, a needle tip at the distal end of the barrel and a proximal end opposite the needle tip of the barrel; Having a vertical axis positioned within the barrel to move axially from within to inject fluid into or into the barrel through the needle tip and having at least one ratchet tooth; Extending from the end beyond the barrel and having a sealing piston at the distal end near the needle tip end of the barrel, each of which has a smooth wall of reduced diameter plunger rod for each ratchet tooth. A substantially cylindrical plunger rod having an intake gap comprising proximal to the cheat tooth; Radially mounted on the plunger rod, the latch teeth having a mechanical engagement with the plunger rod and one or more outwardly oriented locking teeth having contacts in frictional contact with the sidewall A spring locking clip in the form of an elastic open wall; The plunger rod freely reciprocates when the spring lock clip is positioned on the intake gap of the plunger rod, and the spring lock clip is caused by frictional engagement of the contact with the side wall as the plunger rod moves. Closed movement of the plunger rod, which is held in a position inside the barrel and cooperates with the latch tooth engaging means with the spring lock clip, means that the latched tooth engaging means of the plunger rod moves the spring lock clip to the plunger. Move in the distal direction with the rod, The spring lock clip and plunger rod allow the syringe to load the drug into the barrel of the volume defined by the predetermined position of the spring lock clip on the plunger rod by the proximal movement of the plunger, After engagement between the ratchet teeth, the distal movement of the plunger rod discharges the drug and moves the spring lock clip inside the barrel, while the plunger rod is frictional between the contact and the inner cylindrical sidewall. Disposable syringe that prevents movement over the entire length of the barrel by formula engagement. The disposable syringe of claim 1, wherein the ratchet teeth engagement means of the plunger rod comprises an inwardly oriented contact element. The disposable syringe of claim 1, wherein the spring lock clip extends around the plunger rod in a range of about 180 ° to less than 360 °. The disposable syringe of claim 1, wherein the spring lock clip extends less than about 180 ° around the plunger rod. The disposable syringe of claim 1, wherein the spring lock clip extends about 27 ° to less than 180 ° around the plunger rod. The disposable syringe of claim 1, wherein the drug containing volume of the barrel is defined to be as small as about 0.1 cc by the initial position of the spring lock clip on the plunger rod. The disposable syringe of claim 1, wherein the spring locking clip biases the plunger rod in axial alignment with respect to the axis of the hollow barrel during movement. The disposable syringe of claim 1, wherein each ratchet tooth is frusto-conical. The disposable syringe of claim 1, wherein each ratchet tooth is beaded. The disposable syringe of claim 1, wherein sealing ends are provided at distal and proximal ends of the plunger rod to provide a sterile chamber for the drug and to prevent unauthorized access to the spring locking clip. The disposable syringe of claim 1, wherein the plunger rod has one or more fracture surfaces having a tensile strength less than the frictional resistance between the sidewall of the barrel and the contact of the spring lock clip. The disposable syringe of claim 1, wherein the plunger rod has two or more intake gaps spaced axially and one or more ratchet teeth are located distal to each of the intake gaps. The disposable syringe of claim 1, wherein the ratchet tooth engagement means bends radially outwardly on the surface of each ratchet tooth as the plunger rod moves upward in a proximal direction. The disposable syringe of claim 1, wherein the ratchet tooth engagement means engaged with the base of the ratchet tooth moves with the plunger rod when the plunger rod moves in the distal direction. The disposable syringe of claim 1, wherein the intake gap comprises a section of the plunger rod of a diameter smaller than the respective ratchet teeth. The disposable syringe of claim 1, wherein the plunger rod is provided with two or more intake gaps, each intake gap positioned between adjacent ratchet teeth of the plunger rod. The disposable syringe of claim 16, wherein the intake gaps are of different lengths. The disposable syringe of claim 1, wherein the intake gap is neutralized by a close movement of the plunger rod in a range in which the spring lock clip is mechanically coupled to the ratchet tooth of the plunger rod. 17. The intake gaps of claim 16 are sequentially neutralized by each proximal movement of the plunger rod in a range in which the spring lock clip is mechanically coupled to a ratchet tooth of the plunger rod adjacent to the intake gap. Disposable syringe.