DE20116321U1 - Disposable safety syringe - Google Patents

Description

DISPOSABLE SAFETY SYRINGE

Area of the utility model

The present utility model relates to a syringe and in particular to a disposable safety syringe. The syringe has a retractable needle which, after use, is drawn into a syringe body by a plunger so that accidental needlestick injuries are prevented.

2. Description of the related art

People working in the health sector are at risk of transmitting infectious diseases through accidental contact with contaminated medical waste. One of the greatest contact risks for people working in the health sector and for people handling medical waste is from accidental needlestick injuries. The risk of a person working in the health sector becoming infected with the HIV virus from accidental needlesticks alone is reported to be 1 in 300. The risks of transmitting other serious diseases to people working in the health sector are even greater.

A new disposable syringe with a retractable needle is therefore intended to solve the problem of accidental needle sticks. The disposable syringe usually has a retractable needle that can be held in place by a plunger. By pulling the plunger, the needle is completely drawn into the syringe body so that the contaminated syringe can be disposed of safely and without the risk of needle stick injuries.

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However, the disposable syringe with the retractable needle can only solve the problem of accidental needlestick injuries in an ideal situation. In practical use, other problems can also arise; for example, the connection between the needle and the plunger is not sufficiently secure when the needle is retracted and can come loose in an undesirable way before the needle is completely retracted into the syringe body. This undesirable

IQ Release can pose a health risk to the user due to the risk of accidental needlestick injury. In addition, air bubbles in the fluid in the syringe must be removed before the injection is administered. With conventional syringes, the user must usually point the needle upwards and tap the syringe body to allow the air bubbles to escape. This process is inconvenient and needs improvement.

The present utility model therefore provides a disposable safety syringe designed to reduce or eliminate the problems mentioned above.

An objective of the present utility model is to provide a disposable safety syringe that prevents people working in the health care sector from being exposed to accidental needlestick injuries, scratches or other hazardous contacts. The syringe includes a syringe body, a connector mounted on a front end of the syringe body, a needle assembly attached to the connector and a plunger that can be pushed into the syringe body. The plunger includes a connector head so that the connector head can hold the connector after the injection process has been completed. Therefore, the needle assembly can be pulled completely into the syringe body by the plunger.

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and the syringe can
Dispose of safely without risk of injury.

then

Another object of the present utility model is to provide a disposable safety syringe having the construction described in the previous object, in which the connection between the connector and the connecting head of the plunger is secure and unwanted detachment of the connector and the connecting head during retraction of the needle assembly is prevented.

Another objective of the present utility model is to provide a disposable safety syringe that is specifically designed to allow air bubbles in the fluid present in the syringe body prior to injection to be easily removed prior to the injection procedure.

Further objectives, advantages and novel features of the

The following detailed description shows the use of the model

Description becomes clearer in conjunction with the accompanying drawings.

In the drawings

Fig. 1 is an exploded perspective view of a disposable safety syringe according to the present utility model;
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Fig. 2 is a perspective view of the assembled syringe;

Fig. 3 is a cross-sectional view of the syringe taken along line 3-3 in Fig. 2;

Fig. 4 is a partially enlarged cross-sectional view showing a front portion of the syringe in which a connecting head securely holds a connector;

Fig. 5 is a cross-sectional view of the syringe after use, wherein a needle assembly is retracted into a syringe body and a plunger is broken off for easy disposal; and
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Fig. 6 is a partially enlarged cross-sectional view showing the connector and the connection head.

Referring to Figs. 1 and 2, there is shown a disposable safety syringe according to the present invention comprising a syringe body (10), a plunger (20), a connector head (28), an upper sealing ring (30), a connector (40), a needle assembly (50) and a lower sealing ring (60).

The syringe body (10) is a hollow cylinder having an open front end and an open rear end. A finger flange (100) is integrally formed with and extends outwardly from the open rear end. Numerous limiting projections (102) are formed on an inner surface of the syringe body (10) near the open rear end. Numerous retaining projections (104) are formed on the inner surface of the syringe body (10) and near the open front end.

Referring to Figs. 1 and 6, the plunger (20) can be pushed into the syringe body (10) and includes a plurality of elongated body members (22), a thumb pad formed at a rear end of the plunger (20), and a plunger (25) formed at a front end of the plunger (20). Each body member (22) is provided with a break line (24) defined near a front end of the plunger (20) so that the body members (22) can be easily broken off and separated from the plunger (25) after the injection process is completed. The plunger (25) includes a holding portion (26) to hold the

the upper sealing ring (30) can be attached. A connecting head (28) of conical shape is molded integrally with the holding part (26). An annular groove (29) is molded in the connecting head (28) and adjacent to the holding part (26). In particular, the annular groove (29) is defined by an abutment surface (292) and a rear surface (294), the rear surface (294) being inclined towards a free end of the connecting head (28).

The connector (40) has a positioning part (42) to

• to which the lower sealing ring (60) can be attached, a tubular part (44) on which the needle assembly (50) can be attached, and a disk-shaped part (46) formed between the positioning part (42) and the tubular part (44). A passage (404) runs longitudinally through the connector (40). An annular slot is formed around the disk-shaped part (46).

(462) for receiving the limiting projections (102), whereby the connector (40) is connected to the open front end of the syringe body (10).

The lower sealing ring (60) to be fitted around the positioning part (42) of the connector (40) has an upper surface (602), a lower surface (603) and a bore (604) defined by the lower sealing ring (60) from the upper surface (602) to the lower surface (603). An annular flange (606) whose shape corresponds to the annular groove (26) of the connecting head (28) extends integrally from the upper surface (602) into the bore (604) to be received in the annular groove (26) defined in the connecting head (28).
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The needle assembly to be mounted on the connector (40)

(50) has a hollow needle (52) which extends out of the needle hub (54), wherein the hollow needle

(52) and the needle hub (54) securely

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A receiving hole (56) intended to receive the tubular part (44) of the connector (40) is defined longitudinally in the needle hub (54).

Referring to Fig. 2 and 3, when assembling the disposable safety syringe, the lower sealing ring (60) is fitted around the positioning part (42) of the connector (40), whereby the bore (604) defined in the lower sealing ring (60) communicates with the passage (404) defined in the connector (40). Then, the connector (40) is assembled into the open front end of the syringe body (10) by inserting the retaining projections (104) of the syringe body (10) into the annular slot (462) of the disk-shaped part

(46) of the connector (40). The upper sealing ring (30) is then placed around the holding part (26) of the piston (20) and the piston (20) pushes the connecting head (28) over the open rear end of the syringe body (10) into the syringe body (10).

The connector head (28) must be adequately pressured to slide over the retaining projections (104) formed near the open rear end of the syringe body (10). Finally, the needle assembly (50) is mounted on the connector (40) by firmly securing the tubular portion (44) of the connector (40) in the receiving hole (56) defined in the needle assembly (50). The syringe is now ready for use. The injection process with the syringe is the same as with the prior art syringes. Since syringes are well known medical instruments and have been used for many years, a detailed description of the injection process with the syringe will be omitted. It should be noted, however, that due to the conical shape of the connector head (28) and the inclination of the rear surface (294) towards a free end of the connector head

(28) air bubbles in the liquid in the syringe body (10) can be easily removed by pointing the needle (52) upwards and the

The piston (20) is pushed a little further into the syringe body (10). This means that the syringe body (10) no longer has to be tapped to remove the air bubbles, as was the case with conventional syringes.

Referring to Fig. 4, after use of the syringe according to the present use model, the piston (20) is pushed further into the syringe body (10) to allow the connection head (28) to be securely connected to the connector (40) by securely receiving the annular flange (606) of the upper sealing ring (60) in the corresponding annular groove (29) defined in the connection head (28).

The plunger (20) is then pulled so that it draws the connector (40) together with the needle assembly (50) into the syringe body (10). Referring to Fig. 5, the needle assembly (50) is pulled until the needle (52) is completely retracted into the syringe body (10) and the limiting projections (102) (better seen in Fig. 2) prevent the connector head (28) from exiting the open rear end of the syringe body (10). The plunger (25) is severed by breaking off the body members (22) of the plunger (20) along the fracture lines (24). Thus, the contaminated needle (52) is contained within the syringe body (10) and the used syringe can be safely disposed of without risk of injury.

From the previous description it can be seen that the utility model has the following advantages:

1. The connection between the connecting head (28) and

the lower sealing ring (60) is secure, and

unwanted loosening when retracting the needle assembly (50) is prevented.

2. The connecting head (28) and the lower sealing ring (60) have a special shape so that the air bubbles can be easily removed from the syringe body (10) before giving an injection.

3. The design of the syringe is simple and suitable for mass production.

Although this utility model has been particularly shown and described with reference to its preferred embodiment, it will be apparent to those skilled in the art that various changes in form and details are possible without departing from the scope of the utility model described in the appended claims.

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Claims (5)

1. Disposable safety syringe, comprising:
a hollow syringe body ( 10 ) having an open front end and an open rear end;
a plunger ( 20 ) insertable into the syringe body ( 10 ) from the open rear end, the plunger ( 20 ) having a front end extending into the syringe body ( 10 ) and an upper sealing ring ( 30 ) securely mounted around the front end;
a connecting head ( 28 ) formed at the front end of the piston ( 20 ), the connecting head ( 28 ) defining a groove ( 29 );
a hollow connector ( 40 ) mounted in the open front end of the piston ( 20 ), the hollow connector ( 40 ) having a positioning portion ( 42 ) and a tubular portion ( 44 );
a lower sealing ring ( 60 ) securely mounted around the locating portion ( 42 ) of the hollow connector ( 40 ), the lower sealing ring ( 60 ) defining a bore ( 604 ) extending through the lower sealing ring ( 60 ) and having a flange ( 606 ) extending into the bore ( 604 ) for receipt in the groove ( 29) defined in the connector head (28 ) ;
a needle assembly ( 50 ) mounted on the connector ( 40 ) having a needle hub ( 54 ) and a needle ( 52 ) extending from the needle hub ( 54 ), the needle hub ( 54 ) defining a receiving hole ( 56 ) configured to allow the tubular portion ( 44 ) to be firmly pressed into the receiving hole ( 56 ),
whereby the connecting head ( 28 ) and the lower sealing ring ( 60 ) can be securely connected to one another after completion of an injection procedure with the disposable safety syringe by securely receiving the flange ( 606 ) in the groove ( 29 ) so that the needle assembly ( 50 ) can be fully retracted into the syringe body ( 10 ) by pulling on the plunger ( 20 ) such that the needle ( 52 ) is securely received in the syringe body ( 10 ) to avoid accidental injury. 2. Disposable safety syringe according to claim 1, wherein the flange ( 606 ) of the lower sealing ring ( 60 ) is shaped as an annular flange ( 606 ). 3. A disposable safety syringe according to claim 2, wherein the groove ( 29 ) defined in the connecting head ( 28 ) is shaped as an annular groove ( 29 ) corresponding to the annular flange ( 606 ). 4. A disposable safety syringe according to claim 1, wherein the flange ( 606 ) is inclined towards a free end of the connecting head ( 28 ) and the groove ( 29 ) is defined according to an inclined shape of the flange ( 606 ) to ensure that the flange ( 606 ) is securely received in the groove ( 29 ). 5. A disposable safety syringe according to claim 3, wherein the annular flange ( 606 ) is inclined towards a free end of the connecting head ( 28 ) and extends into the bore ( 604 ) of the lower sealing ring ( 60 ) and the annular groove ( 29 ) is defined according to an inclined shape of the annular flange ( 606 ) to ensure that the flange ( 606 ) is securely received in the annular groove ( 29 ).