Non-loosening luer nut

• US 4,735,441 A
• Filed: 03/06/1987
• Issued: 04/05/1988
• Est. Priority Date: 06/03/1985
• Status: Expired due to Fees

• Current Assignee: Hewlett-Packard Company (HP Inc.)
• Original Assignee: Hewlett-Packard Company (HP Inc.)
• Inventors: Stephens, Thomas P.
• Primary Examiner(s): NOT, DEFINED
• Application Number:
  US07/022,504
• Time in Patent Office: 396 Days
• Field of Search: 285/332, 285/175, 285/176, 411/417, 411/349, 411/437, 411/549, 411/263, 411/937.1, 411/938, 411/937, 411/937.2
• US Class Current: 285/148.19
• CPC Class Codes: A61M 2039/1033 Swivel nut connectors, e.g. threaded connectors, bayonet-connectors
• CPC Class Codes: A61M 39/10 Tube connectors; Tube couplings A61M39/02 takes precedence; connecting needles to syringes or hubs A61M5/34; connecting catheter tubes to hubs A61M25/0014
• CPC Class Codes: F16B 39/284 Locking by means of elastic deformation F16B39/2825, F16B39/36, F16B39/38 take precedence
• CPC Class Codes: F16L 15/003 with sealing rings

Abstract

An assembly for axially coupling male and female tubes including a nut having internal threads on a polygonally shaped inner surface at one end that can be screwed onto a projection on one of the tubes so as to draw a collar at the other end of the nut into axial contact with a shoulder on the other end of said tubes so as to draw the tubes together, the said projection being such as to ride in said threads at points along the surface of at least one side of said polygon so as to bend it outwardly from its unstressed position.

Claims

1. A Luer nut assembly comprising

a female hollow tube having an axis,

a radial exterior projection at an end of said female tube, said projection having a given periphery in a plane perpendicular to the axis of the tube,

means defining a conical recess in one end of said female tube,

a male hollow tube having an external surface at one end thereof that is conical in shape so as to fit into said conical recess when the ends of said female and male tubes are axially drawn together,

a shoulder formed on the exterior of said male tube at a point adjacent the lower end of said exterior conical surface,

a Luer nut having a body, means defining a cavity in said body having an interior surface extending about an axis, threads formed on said interior surface, said interior surface having a cross-section in a plane perpendicular to said axis that is in the general form of a polygon, and which is enlarged as it approaches one end of said cavity,

said nut having an inwardly extending collar at the other end of said cavity that is coaxial with said surface and through which said male tube passes, said collar being axially more remote from said one end of said cavity than said shoulder, and

the dimensions and shape of the periphery of said projection being such that it contacts said interior surface of said cavity at at least one point.

2. An assembly as set forth in claim 1 wherein the periphery of said exterior projection is circular.

3. An assembly as set forth in claim 1 wherein the periphery of said exterior projection is rectangular.

4. An assembly set forth in claim 1 wherein the periphery of said exterior projection is in the form of parallel lines connected at opposite ends by curved lines.

5. A Luer Nut assembly comprising:

a female tube having a recess within an end thereof;

a male tube having an exterior surface at an end thereof that can form a seal when pressed into the recess of said female tube,

a hollow Luer nut having an axis, an inwardly extending collar at one end thereof, and internal threads about said axis on an interior surface at the other end thereof, said internal surface having a cross-section in a plane perpendicular to said axis that is in the general form of a polygon, the sides of the nut forming said polygon being flexible,

one said tubes having an exterior shoulder that can engage the inside of said collar, and

the other one of said tubes having an exterior projection that can engage said internal threads at an intermediate point of at least one side of the polygon, the dimensions of said projection being such that it forces any side of the polygon with which it is in contact away from said axis so as to create a rotational friction force between such shoulder and said collar.

6. A Luer nut having a body means defining a cavity in said body having an interior surface extending about an axis,

threads formed on said interior surface,

said interior surface having a cross-section in a plane perpendicular to said axis that is in the general form of a polygon, and which is enlarged as it approaches one end of said cavity,

an inwardly extending collar at the other end of said cavity that is coaxial with said surface.

7. A Luer nut as set forth in claim 6 wherein said threads are adapted to provide a given amount of friction torque with a projection on a tube screwed therein and said collar to be adapted to produce less frictional torque with a ridge on a tube inserted therethrough.