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EP-3990054-B1 - ULTRA-LOW WASTE DISPOSABLE SAFETY SYRINGE FOR LOW DOSE INJECTIONS

EP3990054B1EP 3990054 B1EP3990054 B1EP 3990054B1EP-3990054-B1

Inventors

  • BERLER, BARRY B.

Dates

Publication Date
20260506
Application Date
20200624

Claims (9)

  1. A needle and syringe system (10), comprising: a syringe barrel (16); a plunger rod (18) having a plunger head (20) that can reciprocally move within said syringe barrel (16); a needle base (26) affixed to said syringe barrel (16), said needle base (26) having a first end that extends into said syringe barrel (16) and a distal second end that extends beyond said syringe barrel (16), wherein a cavity (40) is formed in said needle base (26) that is accessible from within said syringe barrel (16) and through slots (42) formed in said needle base (26) between said first end and said second end; supports (50) that extend through said slots (42) from within said cavity (40); a protective cover (52) that surrounds said needle base (26) and contacts said supports (50); wherein when said plunger rod (18) is advanced in said syringe barrel (16), said plunger head (20) advances said supports (50) in said cavity (40) and said supports (50) move said protective cover (52) from a first position to a second position, characterised in that said needle base (26) supports a needle (24) and includes a central post (44) having a length longer that the length of the cavity (40), said central post (44) extends through said cavity (40) and partially extends into the syringe barrel (16), wherein said central post (44) and said cavity (40) are concentric and the needle (24) extends through said central post (44) of said needle base (26), said supports (50) extend from an activation ring (48) disposed within said cavity (40); and whereby an annular spacer (46) is disposed in said cavity (40), and said plunger head (20) is configured to move said annular spacer (46) and said annular spacer (46) is configured to move said activation ring (48), and wherein the annular spacer (46) and the activation ring (48) have a combined length that is exactly the same as the length of the central post (44).
  2. The system (10) according to Claim 1, wherein the needle extends (24) from said second end of said needle base (26) when said needle (24) is protected by said protective cover (52) when said protective cover (52) is in said second position.
  3. The system (10) according to Claim 1, wherein said cavity (40) has a length from said first end toward said second of said needle base (26), wherein said annular spacer (46) and said activation ring (48) have a combined length equal to said length of said cavity (40).
  4. The system (10) according to Claim 1, wherein said needle base (26) and said protective cover (52) have a protrusion (56) and depressions (36, 38) that engage and act to retain said protective cover (52) in said first position and said second position.
  5. The system (10) according to Claim 1, wherein said needle base (26) has a central axis and the central post (44) extends through said cavity (40), wherein both said cavity (40) and said central post (44) are concentric with said central axis.
  6. The system (10) according to Claim 5, in which the needle (24) extends into said needle base (26) along said central axis, wherein said needle (24) extends through said central post (44) and is open at said first end of said needle base (26).
  7. The system (10) according to Claim 6, in which the annular spacer (46) is configured to be displaced into said cavity (40) within said needle base (26) as said plunger head (20) is advanced in said syringe barrel (16).
  8. The system (10) according to Claim 7, wherein said supports (50) are moved by said annular spacer (46).
  9. The system (10) according to Claim 8, wherein said protective cover (52) contacts said supports (50) and is moved between said first position and said second position by said supports (50).

Description

Technical Field Of The Invention In general, the present invention relates to syringes that are used to make injections through a needle or cannula. More particularly, the present invention relates to safety syringes that are designed to shield the needle after use and to minimize the amount of injection material retained within the syringe after the syringe is used. Background Art Healthcare professionals perform millions of injections each year. The injections are typically performed using a hypodermic needle and a syringe. The length of the hypodermic needle and the gauge of the needle depend upon the application and whether the injection is intramuscular, subcutaneous, intravenous, or intradermal. The compounds being injected also vary widely. Some injection materials, such as saline, are very inexpensive. However, many pharmaceutical compounds, such as certain gene therapy compounds, can cost tens of thousands of dollars per injection. As such, a fraction of a milliliter of the pharmaceutical can be worth hundreds of dollars. When a traditional hypodermic needle and syringe are used to perform an injection, there is inevitably some volume of injection material that remains within the needle and syringe after the injection is complete. The pharmaceutical material remaining is thrown away with the needle and syringe after the injection. This wasted pharmaceutical material adds up to billions of dollars in wasted pharmaceuticals, when all injections are considered. In the prior art, thought is rarely given to the volume of residual material that inherently remains within a hypodermic syringe and needle. Some needle and syringe assemblies have been designed where a syringe plunger and a needle head make flush contact. Such prior art designs are exemplified by U.S. Patent No. 6,616,636 to Lee and U.S. Patent No. 5,902,270 to Jentzen. However, in a real healthcare environment, such as a hospital, different syringes are used with many different needle heads, depending upon the specific medical application. Some needle head and syringe combinations are efficient in the discharge of pharmaceutical compounds and some are not. The problem becomes more complicated when a needle head and syringe are part of a safety syringe assembly. Safety syringe assemblies are designed to both perform an injection and to provide some mechanism for minimizing the likelihood of a needle stick injury. Needle stick injuries are commonplace among healthcare workers. Needle stick injuries are defined by the United States National Institute of Occupational Safety and Health as injuries caused by needles such as hypodermic needles, blood collection needles, intravenous (IV) stylets, and needles used to connect parts of IV delivery systems. Needle stick injuries can transfer blood-borne pathogens such as Hepatitis B virus, Hepatitis C virus, Human Immunodeficiency Virus (HIV) and Covid-19. For healthcare workers, needle stick injuries are responsible for a significant proportion of these diseases in the healthcare workforce. It has been estimated by the Centers for Disease Control, that in the United States of America, that more than three million healthcare workers are exposed to blood and bodily fluids via needle mishaps each year. Most healthcare workers are trained in procedures for using and disposing of used needles. For example, needles should not be recapped, in order to prevent the potential for needle stick injuries. However, many studies have revealed that recapping is still prevalent among healthcare workers. In an attempt to reduce the number of needle stick injuries, various safety needles have been developed that act to automatically cover a needle the instant the needle is retracted from the skin. This is typically accomplished by advancing a tubular sheath along the shaft of the needle until the sheath covers the tip of the needle. Such prior art is exemplified by U.S. Patent No. 6,626,863, U.S. Patent Application Publication No. 2007/0016140, U.S. Patent Application Publication No. 2007/0016145, and U.S. Patent Application Publication No. 2008/009808. However, integrating a safety mechanism within a needle head typically takes additional room within the needle head. More room in the needle head means that there is more dead space in the needle head where residual pharmaceutical compounds can collect. As a consequence, there are often opposing concerns that must be balanced in a design. The safety features of a design are balanced with the wasted pharmaceutical retained because of the safety features. A need therefore exists for an improved hypodermic needle and syringe assembly where the needle is automatically shielded after an injection and wherein the assembly does not retain any significant volume of the material being injected. This need is met by the present invention as described and claimed below. United States Patent Application Publication No. US 2008/097337 Al discloses a syringe comprising a barrel (11) and