Needle assembly

Abstract: A needle assembly 10 comprises a needle device 11 having a needle base 14 and a hollow needle 12, having a free end 13 which is sharpened or pointed, protruding from the base, with a passageway 15 extending along the needle. An opening 17 to the passageway is provided in proximity to the sharpened end or point of the needle. A needle guard comprising an elongate protective sheath 20 is provided around the needle base and the needle such that the sharpened end of the needle is protected by the sheath. An elongate opening 24 extends along the sheath and the needle can pass through it. First hinge components 30 are located on the sheath. Second hinge components 16 are provided on the base. The first and second hinge components co-operate with each other such that the needle guard is pivotal from a primary position in which the sharpened needle end or point is protected by the sheath, to a secondary position in which the needle point is exposed for use.

Description: THIS INVENTION relates to a needle assembly. WO 90/01348 teaches a guard for a hypodermic syringe needle. The guard includes a needle shroud which is pivotable between open and closed positions, and is provided with releasable locking means to hold the guard respectively in open and closed positions. The shroud has a slit through which the needle passes as the shroud is pivoted, and the slit extends the full length of the shroud. Thus, even when the shroud is locked in its closed position by the locking means, the needle point is not positively trapped within the shroud, and accidental needle prick can still occur, eg on accidental pivoting of the shroud. It is hence an object of the invention to provide means whereby this drawback can at least be reduced. Thus, according to a first aspect of the invention, there is provided a needle assembly, which comprises a needle device having a needle base and a hollow needle, having a pointed free end, protruding from the base, with a passageway thus extending along the needle, and with an opening to the passageway being provided in proximity to the pointed end of the needle; a needle guard comprising a hollow elongate protective sheath around the needle and having a first open end accommodating the needle base and a second closed end in proximity to the needle point, an elongate slot extending from the first end of the sheath to near its second end and through which the needle can pass, and a first pair of openings in the sheath in proximity to its first end, with the openings being aligned with each other and being located on opposite sides of the slot; a pair of complementary pivot pins protruding from the needle base, with each pin being pivotally located in one of the openings such that the sheath can be pivoted from a primary position in which the pointed needle end is protected by the sheath, to a secondary position in which the needle point is exposed for use; characterized in that it includes a pair of secondary openings in the sheath, spaced longitudinally from the first pair of openings and also being capable of accommodating the pivot pins in pivotal fashion, with each secondary opening being connected to its associated first opening by means of a first passageway along which the pivot pin can pass and with the secondary openings being spaced further from the first end of the sheath than the first pair of openings so that the sheath is displaceable in a longitudinal direction with respect to the needle from the position in which the pivot pins are located in the first pair of openings and in which the needle point is aligned with the slot to permit pivoting of the sheath from its primary to its secondary position, to a second position in which the pivot pins are located in the secondary openings and in which the needle point is held captive by a portion of the sheath between the distal end of the slot in the sheath and the second end of the sheath. The needle device can thus be a hypodermic needle, catheter needle, cannula, needles used for introduction of intravenous type cannulas, spinal needles, or the like, used for the injection of, or removal of, fluids or gases parenterally or subcutaneously. The sheath may have a complementary shape to the needle. More particularly, the sheath may be of cylindrical form. While the hinge openings can extend through the sheath, they can instead be in the form of protrusions in which the pins are located. Naturally, the pivot pins can instead be provided on the sheath, and the openings in the needle base, if desired. The length of the slot is thus such that when the sheath is in its first position, the needle is held captive by that portion of the sheath between the distal end of the slot and the second end of the sheath, while when it is in its second position, the needle point passes with clearance through the slot. In other words, in moving the sheath from its first to its second position, it is displaced sufficiently in the direction of the pointed end of the needle so that it is no longer held captive by the needle in its second position. To move the sheath from its second to its first position, it is drawn forward in the direction of the pointed or sharpened end of the needle so that the pivot pins move from the second openings, along the first passageways, to the first openings. The reverse movement takes place to move the sheath from its second to its first position. The assembly may also include a pair of tertiary sheath openings for the pivot pins, the tertiary openings being spaced longitudinally from the secondary openings and located further from the first end of the sheath than the secondary openings, with each tertiary opening being connected to its associated secondary opening by means of a second passageway along which the pivot pin can pass. The widths of the first passageways may be substantially constant, while the widths of the second passageways may taper down from the secondary apertures to the tertiary apertures so that, when the sheath is displaced towards the needle base, the pivot pins can pass with limited clearance through the tertiary passageways, e.g. by flexing the material of the sheath slightly, and are then held captive in the tertiary openings, preventing re-use of the needle. The assembly may include an anchoring member attached to the needle base, with the pivot pins the mounted to the anchoring member. In one embodiment of the invention, the anchoring member may be in the form of a ring around the needle base. In another embodiment of the invention, the anchoring member may be in the form of a clip gripping the needle base. According to a second aspect of the invention, there is provided a needle guard for a needle device comprising a needle base, a hollow needle, having a pointed free end, protruding from the base, with a passageway thus extending along the needle, and with an opening to the passageway being provided in proximity to the pointed end of the needle, and a pair of pivot pins protruding from opposite sides of the needle base, the needle guard comprising a hollow elongate protective sheath adapted to fit around the needle of the needle device and having a first open end for accommodating the needle base and a second closed end which will be in proximity to the needle point; an elongate slot extending from the first end of the sheath to near its second end and through which the needle can pass; a first pair of openings in the sheath in proximity to its first end, with the openings being aligned with each other and being located on opposite sides of the slot, the openings being adapted to co-operate with the pair of pivot pins such that the sheath can be pivoted, in use, from a primary position in which the pointed needle end is protected by the sheath, to a secondary position in which the needle point is exposed for use, characterized therein that the needle guard also comprises a pair of secondary openings in the sheath, spaced longitudinally from the first pair of openings and also being capable of accommodating the pivot pins in pivotal fashion, with each secondary opening being connected to its associated first opening by means of a first passageway along which the pivot pin can pass and with the second opening being spaced further from the first end of the sheath and the first pair of openings so that the sheath is displaceable in a longitudinal direction with respect to the needle from the position in which the pivot pins are located in the first pair of openings and in which the needle point is aligned with the slot to permit pivoting of the sheath from its primary to its secondary position, to a second position in which the pivot pins are located in the secondary openings and in which the needle point is held captive by a portion of the sheath between the distal end of the slot and the sheath, and the second end of the sheath. The needle guard may include an anchoring member attachable to the needle base and on which the second hinge component is located. The invention will now be described by way of non limiting example with reference to the accompanying diagrammatic drawings in which: FIGURE 1 shows an exploded three-dimensional view of a needle assembly according to one embodiment of the invention; FIGURE 2 shows a non-exploded side view of the assembly of Figure 1; FIGURE 3 shows an enlarged view of a portion of Figure 1; FIGURES 4 and 5 show three dimensional views of parts of needle assemblies according to further embodiments of the invention. Referring to Figures 1 to 3 of the drawings, reference numeral 100 generally indicates a needle assembly according to one embodiment of the invention. The assembly 100 comprises a hypodermic needle device, generally indicated by reference numeral 102. The needle device 102 includes a needle 104 having a pointed or sharpened distal end 106, and a cylindrical base 108 at the other end of the needle 104. A passageway 110 extends through the needle base and along the needle, and terminates in an opening 112 at the sharpened end 106 of the needle. Diametrically opposed pivot pins 114 protrude radially from opposite sides of the needle base 108. The assembly 100 also includes a more-or-less cylindrical sheath, generally indicated by reference numeral 120. The sheath 120 has a cylindrical portion 122 of more-or-less constant diameter, with the one end 124 of the portion 122 being closed off. The sheath 120 also has a portion 126, the internal diameter of which is somewhat larger than that of the portion 122 and within which the needle base 108 is accommodated snugly. The end 128 of the portion 126 is open. A longitudinally extending slot 130 extends along the portions 126, 122 and terminates some distance from the end 124 of the sheath so that the sheath portion 122 includes a portion 132, in proximity to the sheath end 124, which is unbroken circumferentially. In the portion 126 of the sheath 120 are provided diametrically opposed pairs of apertures 134, 136 and 138. The apertures 136 are spaced longitudinally from the apertures 134, towards the end 128 of the sheath, while the apertures 138 are spaced longitudinally from the apertures 134, in the direction of the closed end 124 of the sheath. Each aperture 136 is connected to its associated aperture 134 by means of a constant-width passageway 140, while each aperture 138 is connected to its associated aperture 134 by means of a passageway 142. The width of the passageway 142 tapers down from the aperture 134 to the aperture 138. One of the pivot pins 114 can be accommodated pivotally in one of the apertures 134, 136 and 138, while the width of the passageway 140 is sufficient for the pivot pin 114 to pass slidingly therethrough. However, the width of the passageway 142, at its narrowest, is such that the pivot pin cannot readily pass therethrough and some force must be used to effect this, with the passage of the pivot pin 114 along the passageway 142 only being possible as a result of some flexing, albeit of a minute scale, of the material of the sheath. The sheath 120 is of plastics material such as polyethylene or polypropylene. A pair of spaced cheek plates 144 protrude outwardly from the end 128 of the sheath and the cheek plates are connected together by means of a arcuate bridging portion 146. In use, the assembly 100 is supplied with the sheath 120 located in a primary inoperative position as indicated in Figure 2, ie with the pivot pins 114 located in the apertures 134 and the needle point 106 being held captive by the portion 132 of the sheath. When it is desired to use the needle 104, the sheath 120, while it is still in its inoperative position as indicated in Figure 2, is moved forwardly, using one hand only, in the direction of arrow 148, with the pivot pins 114 sliding along the passageways 140, until the pivot pins nestle in the apertures 136. The sheath 120 can then be pivoted, using one hand only, to a secondary or operative position, as indicated in broken line in Figure 2, in which the needle point 106 is exposed. The cheek plates 144 and the bridging portion 146, which engage the needle base 108, or a portion of the syringe (not shown) to which the needle is fitted, serve to limit the degree to which the sheath can be pivoted about the pivot pins 114. After use, the sheath can then be pivoted back into its inoperative position as indicated in full lines in Figure 2, whereafter it can be displaced in the direction of arrow 150 so that the pivot pins 114 again move along the passageways 140 into the aperture 134 and from there along the passageways 142, under some force, into the apertures 138. These operations can all be performed using one hand only. The pivot pins 114 will thus be held captive in the apertures 138, preventing re-use of the needle 102. The needle point 106 will then nestle within the portion 132 of the sheath in which it is protected so that it cannot accidentally prick, and infect, a handler. Accidental puncturing could lead to infection, e.g. with AIDS or hepatitis virusses, of users such as medical personnel by the contaminated, used needle. This is avoided with the sheath 120, as hereinbefore described. Furthermore, as a result of the hinge arrangement comprising the pivot pins 114, apertures 134, 136 and 138, and the passageways 140, 142 accurate, smooth and easy pivoting and longitudinal movement of the sheath relative to the needle is achieved even when using one hand only, with the sheath thus being located accurately and effortlessly over the needle when it is moved to its inoperative position. The sheath is furthermore held captive on the needle base to prevent accidental removal or dislodgement of the sheath from the needle device. Referring to Figure 4, reference numeral 200 generally indicates a needle assembly according to another embodiment of the invention. Parts of the assembly 200 which are the same or similar to those of the needle assembly hereinbefore described, are indicated with the same reference numerals. The assembly 200 includes a ring 202 of plastics material, which fits around the needle base 108, with the pivot pins 114 protruding from the ring 202 rather than from the needle base. The ring can grip the needle base frictionally or it can be fixed thereto, e.g. by means of an adhesive. Referring to Figure 5, reference numeral 250 generally indicates a needle assembly according to a still further embodiment of the invention. Parts of the assembly 250 which are the same or similar to those of the needle assemblies hereinbefore described, are indicated with the same reference numerals. The assembly 250 includes a clip 252 which grips the needle base 108 frictionally, with pivot pins protruding from the clip 252 rather than from the needle base. The clip 252 is more-or-less horseshoe-shaped in cross-section. Needle guards in accordance with the invention and incorporating the ring 202 or clip 252 can thus be used on existing needle devices, to provide the protection as hereinbefore described.

Claims: A needle assembly (100) comprising a needle device (102) having a needle base (108) and a hollow needle (104), having a pointed free end (106), protruding from the base, with a passageway (110) thus extending along the needle, and with an opening (112) to the passageway being provided in proximity to the pointed end of the needle; a needle guard comprising a hollow elongate protective sheath (120) around the needle and having a first open end (128) accommodating the needle base and a second closed end (124) in proximity to the needle point, an elongate slot (130) extending from the first end of the sheath to near its second end and through which the needle can pass, and a first pair of openings (136) in the sheath in proximity to its first end, with the openings being aligned with each other and being located on opposite sides of the slot; a pair of complementary pivot pins (114) protruding from the needle base, with each pin being pivotally located in one of the openings such that the sheath (120) can be pivoted from a primary position in which the pointed needle end (106) is protected by the sheath, to a secondary position in which the needle point is exposed for use; characterized in that it includes a pair of secondary openings (134) in the sheath (120), spaced longitudinally from the first pair of openings (136) and also being capable of accommodating the pivot pins (114) in pivotal fashion, with each secondary opening being connected to its associated first opening by means of a first passageway (140) along which the pivot pin can pass and with the secondary openings being spaced further from the first end (128) of the sheath than the first pair of openings so that the sheath is displaceable in a longitudinal direction with respect to the needle (104) from the position in which the pivot pins are located in the first pair of openings (136) and in which the needle point (106) is aligned with the slot to permit pivoting of the sheath from its primary to its secondary position, to a second position in which the pivot pins are located in the secondary openings (134) and in which the needle point is held captive by a portion of the sheath between the distal end of the slot in the sheath and the second end (124) of the sheath. A needle assembly according to Claim 1, characterized in that it includes a pair of tertiary sheath openings (138) for the pivot pins (114), the tertiary openings being spaced longitudinally from the secondary openings (134) and located further from the first end (128) of the sheath (120) than the secondary openings, with each tertiary opening being connected to its associated secondary opening by means of a second passageway (142) along which the pivot pin can pass. A needle assembly according to Claim 2, characterized in that the widths of the first passageways (140) are substantially constant, while the widths of the second passageways (142) taper down from the secondary openings (134) to the tertiary openings (138) so that, when the sheath (120) is displaced towards the needle base (108), the pivot pins (114) can pass with limited clearance through the second passageways and are then held captive in the tertiary openings, preventing re-use of the needle. A needle assembly according to any one of Claims 1 to 3 inclusive, characterized in that it includes an anchoring member (202, 252) attached to the needle base (108) and from which the pivot pins protrude. A needle assembly according to Claim 4, characterized in that the anchoring member is in the form of a ring (202) around the needle base (108). A needle assembly according to Claim 4, wherein the anchoring member is in the form of a clip (252) gripping the needle base (108). A needle guard for a needle device (102) comprising a needle base (108), a hollow needle (104), having a pointed free end (106), protruding from the base, with a passageway (110) thus extending along the needle, and with an opening (112) to the passageway being provided in proximity to the pointed end of the needle, and a pair of pivot pins (114) protruding from opposite sides of the needle base (108), the needle guard comprising a hollow elongate protective sheath (120) adapted to fit around the needle of the needle device and having a first open end (128) for accommodating the needle base and a second closed end (124) which will be in proximity to the needle point; an elongate slot (130) extending from the first end of the sheath to near its second end and through which the needle can pass; a first pair of openings (136) in the sheath in proximity to its first end, with the openings being aligned with each other and being located on opposite sides of the slot, the openings being adapted to co-operate with the pair of pivot pins (114) such that the sheath (120) can be pivoted, in use, from a primary position in which the pointed needle end is protected by the sheath, to a secondary position in which the needle point is exposed for use, characterized therein that the needle guard also comprises a pair of secondary openings (134) in the sheath (120), spaced longitudinally from the first pair of openings (136) and also being capable of accommodating the pivot pins (114) in pivotal fashion, with each secondary opening being connected to its associated first opening by means of a first passageway (140) along which the pivot pin can pass and with the second opening being spaced further from the first end (128) of the sheath and the first pair of openings so that the sheath is displaceable in a longitudinal direction with respect to the needle (104) from the position in which the pivot pins are located in the first pair of openings (136) and in which the needle point (106) is aligned with the slot to permit pivoting of the sheath from its primary to its secondary position, to a second position in which the pivot pins are located in the secondary openings (134) and in which the needle point is held captive by a portion of the sheath between the distal end of the slot and the sheath, and the second end (124) of the sheath. A needle guard according to Claim 7, characterized in that it includes an anchoring member (202,252) attachable to the needle base (108) and on which the pivot pins (114) are located. A needle guard according to Claim 8, characterized in that the anchoring member is in the form of a ring (202) for fitting around the needle base (108). A needle guard according to Claim 8, characterized in that the anchoring member is in the form of a clip (252) for gripping the needle base (108). A needle guard according to any one of Claims 7 to 10 inclusive, characterized in that it includes a pair of tertiary sheath openings (138) for the pivot pins (114), the tertiary openings being spaced longitudinally from the secondary openings (134) and located further from the first end (128) of the sheath (120) than the secondary openings, with each tertiary opening being connected to its associated secondary opening by means of a second passageway (142) along which the pivot pin can pass. A needle guard according to Claim 11, characterized in that the widths of the first passageways (140) are substantially constant while the widths of the second passageways (142) taper down from the secondary openings (134) to the tertiary openings (136) so that, when the sheath (120) is displaced towards the needle base (108), the pivot pins (114) can pass with limited clearance through the second passageways and are then held captive in the tertiary openings, preventing re-use of the needle.

Inventors: PATERSON DONALD WELLWOOD, PATERSON, DONALD WELLWOOD
Applicants: PATERSON DONALD WELLWOOD, PATERSON, DONALD WELLWOOD
Application year: 1991
Main classification: A61M5
IPC codes: A61M5