Positive locking push-on precision 3.5 mm or 2.4 mm connector for an oscilloscope probe

• US 7,354,289 B2
• Filed: 05/30/2006
• Issued: 04/08/2008
• Est. Priority Date: 05/30/2006
• Status: Expired due to Fees

• Current Assignee: Agilent Technologies, Inc.
• Original Assignee: Agilent Technologies, Inc.
• Inventors: Cannon, James E.
• Primary Examiner(s): Gilman; Alexander
• Application Number:
  US11/442,814
• Publication Number:
  US 20070281532A1
• Time in Patent Office: 679 Days
• Field of Search: 439/314, 439/318, 439/332, 439/317, 439/320, 439/352
• US Class Current: 439/314
• CPC Class Codes: G01R 1/06772 High frequency probes
• CPC Class Codes: G01R 1/06788 Hand-held or hand-manipulated probes, e.g. for oscilloscopes or for portable test instruments end pieces terminating in a probe H01R11/18
• CPC Class Codes: H01R 13/625 Casing or ring with bayonet engagement

Abstract

A positive locking push-on 3.5 mm (or other diameter, such as 2.4 mm) connector is provided by retaining an existing bayonet lug and latch style push-on latch mechanism and associated male and female outer conductor shells, but which is sized for 3.5 mm use, while providing SMA/APC-3.5 style male and female center conductor pins that are held in place within their respective outer conductor shells by RF beads that are part of a unitized transmission line subassembly. Alteration of certain axial dimensions of the outer conductor shells prevents the accidental mating of the 3.5 mm bayonet connector with a BNC connector of the opposite gender, and does so in a way that prevents damage to any of the center pins.

Claims

1. A female bayonet connector comprising:

a first shell having first and second ends and also having a first bore therethrough;

a plurality of bayonet lugs disposed upon an outer surface of the first shell and proximate the first end thereof;

a second shell having third and fourth ends, coupled at the third end to the second end of the first shell, and having a second bore therethrough that is coaxial with the first bore;

the first bore having a first region of diameter reduction creating a first shoulder, the first region of diameter reduction proximate, but a first selected distance from, the first end, and the first region of diameter reduction being between the first shoulder and the first end;

the second bore having a second region of diameter reduction creating a second shoulder, the second region of diameter reduction proximate, but a first selected distance from, the fourth end, and the second region of diameter reduction being between the second shoulder and the fourth end;

first and second RF beads each of circular cross section and each having parallel end surfaces the thickness of the RF bead apart, each RF bead having a bore therethrough centered in the end surfaces;

a cylindrical sleeve having an outer diameter that fits within the first and second bores and also having within a central region an inner diameter less than the diameter of the circular cross section, the cylindrical sleeve having opposing fifth and sixth ends, proximate each of which the inside diameter increases to accept the circular cross section and form respective third and fourth shoulders, the extent of the third and fourth shoulders along the axis of the cylindrical sleeve being less than or equal to the thickness of the RF beads;

the first RF bead disposed against the third shoulder and the second RF bead disposed against the fourth shoulder;

first and second RF connector center pins, each having a threaded reduced diameter portion depending from a diameter reduction at a shoulder and extending for a distance longer than the thickness of the RF beads, each of the first and second RF connector center pins entering the bore of a respective one of the first and second RF beads and abutting a respective one of the parallel end surfaces;

a connecting center rod of diameter greater than the bores in the RF beads and threadably coupled at each end to a respective one of the reduced diameter portions of the first and second RF connector center pins;

the inner diameter of the cylindrical sleeve and the diameter of the connecting center rod forming a coaxial transmission line of selected characteristic impedance;

the cylindrical sleeve disposed within the first and second bores, the fifth end abutting the first shoulder and the sixth end abutting the second shoulder;

a female end of the first RF connector center pin extending beyond the first region of diameter reduction in a direction toward the first end of the first shell, but remaining a selected distance inside the first bore; and

the second RF connector center pin forming at the fourth end of the second shell an RF connector that mates with a selected style of RF connector.

2. A female bayonet connector as in claim 1, wherein the first bore at the first end of the first shell forms an aperture that is too small to admit the inner male shell of a male BNC connector.

3. A female bayonet connector as in claim 1, wherein the first RF connector center pin is recessed with the first bore of the first shell to an extent that it cannot contact the male center pin of a male BNC connector.

4. A female bayonet connector as in claim 1, wherein the RF connector formed by the second RF connector center pin and the fourth end of the second shell is an APC-3.5 connector.

5. A female bayonet connector as in claim 1, wherein the RF connector formed by the second RF connector center pin and the fourth end of the second shell is an SMA connector.