Patent Description:
The present invention relates to safety modules, and more particularly, to safety modules with automatic needle retraction.

Needle sharps safety is a growing and important aspect of medical devices. Regulatory and market forces have both driven the need for a reliable way of protecting healthcare professionals, custodial personnel and users from needle stick injury. The ability to protect users and personnel from needle stick injury is a critical aspect that influences the market success of a medical device.

The introduction of fluids into a patient using a catheter and insertion device is known. For intravenous infusion, a common insertion device is an introducer needle received in a catheter. Currently there are several devices that prevent needle stick injury and enable the safe disposal of an introducer needle. These devices are often complicated, expensive and/or difficult to manufacture. Additionally, some previous devices have shown actuation inconsistencies throughout their operating window.

As such, it may be appreciated that there is a continuing need for a new and improved safety module for an insertion needle that addresses the problems noted above and is simple and low-cost to manufacture. Embodiments of the present invention substantially fulfill this need.

<CIT>, <CIT>, <CIT> and <CIT> described background art for the present invention.

In accordance with an aspect of the present invention, a needle assembly comprises a needle having a sharpened end and an opposing end, and a needle tip shield for shielding the needle. The needle tip shield comprises a needle shield connectable to a base, and a needle hub fixedly connected to the opposing end of the needle. The needle shield and needle hub are displaceable relative to each other from a first state in which the sharpened end of the needle is exposed outside the needle shield, to a second state in which the sharpened end of the needle is shielded by the needle shield. The needle tip shield also includes an actuation button movably connected to the needle hub to maintain the needle shield and needle hub in a releasable locked state in a first button position relative to the needle hub, and to permit the needle shield and needle hub to displace relative to each other in a second button position relative to the needle hub.

In accordance with another aspect of the present invention, a needle assembly comprises a needle having a sharpened end and an opposing end, the needle being insertable through a base, the base having a column extending proximally from the base and a head extending from the column forming an undercut between the base and the head. The needle assembly also includes a needle tip shield which comprises a needle hub releasably engaged with the base, the needle hub being fixedly connected to the opposing end of the needle and having an inner recess; an actuation button disposed on an outer wall of the needle hub; a needle shield, having a distal shield aperture, movably disposed in the inner recess, wherein in a first state of the needle shield relative to the needle hub, in which the sharpened end of the needle is exposed outside the needle shield, the actuation button extends through a distal aperture on the needle shield and engages the undercut on the base to releasably lock the needle shield and needle hub together and releasably engage the needle shield and the needle hub with the base; and a biasing element biasing the needle hub and the needle shield axially apart. Displacement of the actuation member relative to the needle hub releases the needle hub and needle shield from the base and releases the biasing element, and the needle shield displaces relative to the needle hub to cover the sharpened end of the needle.

The above and/or other aspects and advantages of embodiments of the invention will be more readily appreciated from the following detailed description, taken in conjunction with the accompanying drawings, in which:.

Reference will now be made in detail to embodiments of the present invention, which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. The embodiments described herein exemplify, but do not limit, the present invention by referring to the drawings.

It will be understood by one skilled in the art that this disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the drawings. The embodiments herein are capable o of being modified, practiced or carried out in various ways. Also, it will be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. Unless limited otherwise, the terms "connected," "coupled," and "mounted," and variations thereof herein are used broadly and encompass direct and indirect connections, couplings, and mountings. In addition, the terms "connected" and "coupled" and variations thereof are not restricted to physical or mechanical connections or couplings. Further, terms such as up, down, bottom, and top are relative, and are employed to aid illustration, but are not limiting.

<FIG> illustrates an exemplary embodiment of an infusion set assembly incorporating a needle tip shield <NUM> in accordance with the present invention. The infusion set assembly includes an introducer needle hub <NUM>, a spring <NUM> and a needle shield <NUM> engaged with an infusion set base <NUM> via an actuation button <NUM>. The needle tip shield <NUM> is mounted in an insertion device <NUM>.

<FIG> is a perspective view of the needle tip shield <NUM> engaged with the infusion set base <NUM> after being removed from the insertion device <NUM>. As shown, the actuation button <NUM> is disposed on an outer wall <NUM> of the needle hub <NUM>. In one exemplary embodiment, the needle hub <NUM> includes ratchet teeth <NUM> on the outer wall <NUM> that engage with a pawl structure <NUM> on an inner surface of the actuation button <NUM> to maintain the connection of the actuation button <NUM> with the needle hub <NUM>.

<FIG> further illustrates features of the needle tip shield <NUM> in a first loaded state prior to actuation of the actuation button <NUM> and removal of the needle tip shield <NUM> from the base <NUM>. As shown, the base <NUM> includes a columnar post <NUM> surrounding an internal cavity <NUM>. A head <NUM> is disposed at the proximal end of the post <NUM>. The head <NUM> may be configured in a mushroom-shape.

As shown in <FIG> and <FIG>, the needle shield <NUM> for selectively covering a distal end of a needle <NUM> includes a circumferential outer wall <NUM> with a proximal end <NUM> and a distal end <NUM>. The proximal end <NUM> includes a proximal opening <NUM> and the distal end <NUM> includes a distal surface <NUM> with a distal opening <NUM> extending therethrough. A passageway <NUM> is formed by the outer wall <NUM> and extends between the proximal opening <NUM> and the distal opening <NUM>. A transverse aperture <NUM> is formed in the outer wall <NUM> proximal to the distal surface <NUM>. Additionally, proximal protrusions <NUM> are formed on the outer wall <NUM> at the proximal end <NUM> of the needle shield <NUM>. The needle shield <NUM> also includes a shield shelf <NUM> extending radially inward in passageway <NUM>, with an opening <NUM> for receiving the insertion needle <NUM>.

The needle hub <NUM> can be movably disposed in the passageway <NUM> and along the outer wall <NUM> of the needle shield <NUM>. The needle hub <NUM> includes a proximal end <NUM>, a distal end <NUM> with an inner sidewall <NUM> and outer sidewall <NUM> extending therebetween. The inner sidewall <NUM> and outer sidewall <NUM> are connected at the proximal end <NUM> of the needle hub <NUM>, and may be coaxial with a recess <NUM> formed therebetween. A hub shelf <NUM> extends radially inside of the inner sidewall <NUM> with an opening <NUM> for receiving the insertion needle <NUM>. According to one embodiment, the insertion needle <NUM> is fixedly connected within the hub shelf <NUM>. The needle hub outer sidewall <NUM> includes an aperture <NUM> proximal to the distal end <NUM>. A hub flange <NUM> is disposed at an upper portion of the aperture <NUM> and a hub distal portion <NUM> is disposed at a lower portion of the aperture <NUM>.

Referring back to <FIG>, the actuation button <NUM> may have a circular shape defining an opening <NUM>. The actuation button includes a latch <NUM> extending into the opening <NUM>, and the latch <NUM> may be disposed on a lower portion of the actuation button <NUM> (see <FIG>).

As illustrated in <FIG>, the infusion set base <NUM> can be removably engaged with the actuation button <NUM> via an undercut <NUM> formed between the column <NUM> and the head <NUM>. When the actuation button <NUM> is in a first, non-activated state, the latch <NUM> of the actuation button <NUM> is received in the distal aperture <NUM> of the needle hub <NUM>, the distal aperture <NUM> of the needle shield <NUM> and in the undercut <NUM> of the infusion set base <NUM>. In the first state the head <NUM> of the infusion set base <NUM> is received in the needle shield passage <NUM>. The spring <NUM> is disposed between the hub shelf <NUM> and the needle shield shelf <NUM>, and is compressed when the needle tip shield is in the first state shown in <FIG> and <FIG>.

<FIG> illustrates that the actuation button <NUM> has moved to the right to unlock the needle shield <NUM> and needle hub <NUM> from the infusion set base <NUM>. Preferably, the operational direction in which the activation button <NUM> moves in advancing from the first to the second state is perpendicular to the longitudinal axis of the needle hub <NUM>. As shown in <FIG>, when the activation button <NUM> is in the second state, the latch <NUM> of the actuation button <NUM> is disengaged from the undercut <NUM> of the infusion set base <NUM> and the distal aperture <NUM> of the needle shield <NUM>. Engagement is maintained between the actuation button <NUM> and the outer wall <NUM> of the needle hub <NUM> by the ratchet teeth <NUM> on the outer wall <NUM> of the needle hub <NUM> and pawl structure <NUM> on the inner surface of the actuation button <NUM>.

Once the latch <NUM> is removed from the distal aperture <NUM> of the needle shield <NUM>, the spring displaces the needle hub <NUM> proximally relative to the needle shield <NUM>. The needle shield <NUM> remains stationary relative to the base <NUM> (see <FIG>).

Driven by the spring <NUM>, the needle hub <NUM> and the needle shield <NUM> move apart from one another until the proximal protrusion <NUM> on the needle shield <NUM> engages an inner portion <NUM> of the distal portion <NUM> and a locking latch <NUM> disposed on the needle shield <NUM> passes the distal end of the needle hub and locks the needle hub <NUM> and needle shield <NUM> in a shielded state (see <FIG>). In the second state, the needle shield <NUM> can be removed from the head <NUM> of the infusion set base <NUM> (see <FIG>).

<FIG> and <FIG> illustrate the fully deployed state in which the needle hub <NUM> has fully displaced and the needle tip shield <NUM> has been removed from the base <NUM>. The introducer needle <NUM> is drawn into the needle shield opening <NUM>. The needle shield <NUM> surrounds and conceals the introducer needle <NUM> so that an average finger, represented by sphere <NUM>, will not fit through the distal opening <NUM> of the needle shield. Therefore, a user is provided with a mechanism to protect from an accidental needle stick.

<FIG> illustrates an alternative embodiment of the needle tip shield <NUM> in which the actuation button <NUM> includes a lever <NUM> including a push tab <NUM>, a fulcrum <NUM> and a lower portion <NUM>. As shown in <FIG>, the needle tip shield <NUM> includes an introducer needle hub <NUM>, a spring <NUM> and a needle shield <NUM> engaged with an infusion set base <NUM> via the actuation button <NUM>. The introducer needle <NUM> passes through a flexible catheter <NUM> that extends from the infusion set base <NUM>. The needle tip shield <NUM> is mounted in an insertion device <NUM>.

<FIG> is a perspective view of the needle tip shield <NUM> engaged with the infusion set base <NUM> after the insertion device <NUM> has been removed. The actuation button <NUM> is in a first state prior to actuation. As shown, the actuation button <NUM> is disposed on an outer wall <NUM> of the needle hub <NUM>. In one exemplary embodiment, the needle hub <NUM> includes ratchet teeth <NUM> on the outer wall <NUM> that engages with a pawl structure <NUM> on an inner surface of the actuation button <NUM> to maintain the connection of the actuation button <NUM> with the needle hub <NUM>.

<FIG> illustrates how the push tab <NUM> moves to the right to unlock the needle shield <NUM> and needle hub <NUM> from the infusion set base <NUM>. Preferably, as a user presses the push tab <NUM>, a force is imparted on the needle hub <NUM> at the fulcrum <NUM>. As shown in <FIG>, with the force of the push tab <NUM> applied to the right, motion is initiated on the lower portion <NUM> of the lever <NUM> to the left. <FIG> illustrates the actuation button <NUM> in a second state subsequent to actuation. In the second state, a latch <NUM> of the actuation button <NUM> is disengaged from an undercut <NUM> of the infusion set base <NUM> and a distal aperture <NUM> of the needle shield <NUM>.

Once the latch <NUM> is removed from the distal aperture <NUM> of the needle shield <NUM>, the spring <NUM> displaces the needle hub <NUM> proximally relative to the needle shield <NUM>. The needle shield <NUM> remains stationary relative to the base <NUM>. Driven by the spring <NUM>, the needle hub <NUM> and the needle shield <NUM> continue to move apart from one another until a proximal protrusion <NUM> on the needle shield <NUM> engages an inner part of a distal portion <NUM> and a locking latch <NUM> disposed on the needle shield <NUM> locks the needle hub <NUM> and needle shield <NUM> in a shielded state (see <FIG>). After the button <NUM> is actuated, the needle shield <NUM> can be removed from a head <NUM> of the infusion set base <NUM> (see, e.g., <FIG>).

<FIG> and <FIG> illustrate the state in which the needle hub <NUM> has fully displaced relative to the needle shield <NUM>. The introducer needle <NUM> is drawn out of the catheter <NUM> and into the needle shield opening <NUM>. The needle shield <NUM> surrounds and conceals the introducer needle <NUM> so that an average finger represented by sphere <NUM> will not fit through the distal opening <NUM> of the needle shield. Therefore, a user is provided with a mechanism to protect from an accidental needle stick.

Claim 1:
A needle assembly for an infusion set, comprising:
a needle (<NUM>) having a sharpened end and an opposing end; and
a needle tip shield (<NUM>) for shielding the needle, comprising:
a needle shield (<NUM>) connectable to an infusion set base (<NUM>);
a needle hub (<NUM>) fixedly connected to the opposing end of the needle, wherein the needle shield and needle hub are displaceable relative to each other from a first state, in which the sharpened end of the needle is exposed outside the needle shield, to a second state, in which the sharpened end of the needle is shielded by the needle shield; and
an actuation button (<NUM>) movably connected to the needle hub and movable relative to the needle hub from a first button state to a second button state;
characterized in that:
wherein the actuation button includes a lower portion (<NUM>) connected to a lever (<NUM>) having a fulcrum (<NUM>) and a push tab (<NUM>) at a free end of the lever; and
wherein actuation of the actuation button by a user pressing the push tab in a first direction causes the fulcrum to contact the needle hub and move the lower portion to travel in a second direction opposite to the first direction from the first button state to the second button state.