Fiber optic connectors and transceiver test devices

• US 6,454,464 B1
• Filed: 08/23/2001
• Issued: 09/24/2002
• Est. Priority Date: 12/28/1998
• Status: Expired due to Fees

• Current Assignee: Computer Crafts, Inc.
• Original Assignee: Computer Crafts, Inc.
• Inventors: Nolan, Richard G.
• Primary Examiner(s): Sanghavi, Hemang
• Assistant Examiner(s): ROJAS, OMAR R
• Application Number:
  US09/938,143
• Time in Patent Office: 397 Days
• Field of Search: 385/52, 385/62, 385/70, 385/72, 385/78, 385/81, 385/82, 385/58, 385/60
• US Class Current: 385/60
• CPC Class Codes: G02B 6/3807 Dismountable connectors, i.e. comprising plugs
• CPC Class Codes: G02B 6/3823 containing surplus lengths, internal fibre loops provisionally see also G02B6/444
• CPC Class Codes: G02B 6/3827 Wrap-back connectors, i.e. containing a fibre having an U shape
• CPC Class Codes: G02B 6/3831 comprising a keying element on the plug or adapter, e.g. to forbid wrong connection keying element on the ferrule G02B6/3851; keying element for electrical coupling H01R13/64
• CPC Class Codes: G02B 6/3833 Details of mounting fibres in ferrules; Assembly methods; Manufacture
• CPC Class Codes: G02B 6/3846 with fibre stubs
• CPC Class Codes: G02B 6/3869 Mounting ferrules to connector body, i.e. plugs
• CPC Class Codes: G02B 6/3875 Floatingly supported sleeves
• CPC Class Codes: G02B 6/3885 Multicore or multichannel optical connectors, i.e. one single ferrule containing more than one fibre, e.g. ribbon type optical ribbon cable G02B6/4403, G02B6/448
• CPC Class Codes: G02B 6/38875 Protection from bending or twisting
• CPC Class Codes: G02B 6/3888 Protection from over-extension or over-compression
• CPC Class Codes: G02B 6/3893 Push-pull type, e.g. snap-in, push-on
• CPC Class Codes: G02B 6/3897 Connectors fixed to housings, casing, frames or circuit boards G02B6/44528 takes precedence
• CPC Class Codes: G02B 6/4246 Bidirectionally operating package structures

Abstract

A fiber optic connector in such as a male MT-RJ connector has a ferrule fixed to the housing. Ferrule-to-ferrule alignment is provided by the floating ferrule in the mating female MT-RJ connector. A field-installable connector includes a field termination unit with fiber stubs and index matching gel for receiving the cut ends of optical fibers. The fiber stubs extend into the ferrule of the connector. A loopback test unit includes a ferrule and housing like those of a standard connector. A fiber loop has both ends lodged in the fiber bores of the ferrule so that the loop will connect the transmitter of a transceiver to the receiver of the same transceiver when the unit is engaged in the connector of the transceiver. The fiber loop is held within a boot attached to the housing or ferrule so that the entire unit can be conveniently installed and removed, and so that numerous loopback testers can be used simultaneously even when the device under test has numerous closely-spaced transceivers.

Claims

1. A male MT-RJ connector having:

(a) a housing insertable within an MT-RJ socket;

(b) a ferrule mounted in said housing in fixed position so that the ferrule cannot be displaced relative to the housing during connection, said ferrule having a front face and having fiber bores extending to said front face; and

(c) alignment pins projecting from said ferrule.

2. A connector as claimed in claim 1 further comprising a field termination unit having fiber bores therein, and pre-installed fiber segments extending from said field termination unit fiber bores and extending in the fiber bores of the ferrule to the front face of the ferrule.

3. A connector as claimed in claim 2 wherein said field termination unit is disposed in said housing immediately behind said ferrule, the connector further comprising a fitting retaining said field termination unit in said housing.

4. A connector as claimed in claim 3 wherein said fitting is a crimp nut having a rear portion defining a channel adapted to pass the fibers of a fiber optic cable, said rear end portion being adapted to fit within the jacket and reinforcement of the cable so that the cable can be secured to the crimp nut by a crimp ring encircling the jacket.

5. A connector as claimed in claim 1 further comprising a device disposed in said housing and engaging the rear surface of said ferrule to maintain said ferrule in position within said housing, said pins having heads projecting from the rear of said ferrule, said device engaging said pins to retain said pins against forward and rearward motion relative to said ferrule and housing.

6. A device for use in making a male MT-RJ connector said device having a body adapted to fit within the housing of a male MT-RJ connector, said body defining a forward wall adapted to engage the rear surface of a ferrule and a pair of pin head slots disposed rearwardly of said forward wall, said pin head slots being open to a top surface of the device so that a ferrule with pins therein can be advanced downwardly relative to the device to engage the heads of the pins in the pin head slots.

7. A device as claimed in claim 6 wherein said body defines a generally U-shaped fiber channel open to the top of the device at the rear of the device.

11. A device as claimed in claim 7 wherein said body is adapted to lock to the housing of a male RJ connector when the device is disposed within the housing of the connector.

8. A method of making a male MT-RJ connector comprising the steps of:

(a) assembling the fibers of a fiber optic cable into fiber bores of a ferrule, securing the fibers to the ferrule and polishing the front face of the ferrule and the forward ends of the fibers;

(b) assembling pins into the ferrule so that heads on the pins project rearwardly from the ferrule, and so that the pins project forwardly from the front face of the ferrule;

(c) advancing the ferrule and fibers downwardly into a device so as to engage the heads of the pins in pin head grooves of the device, place the fibers into the device so that the fibers extend from the rear of the device and thereby form a subassembly; and

(d) placing the subassembly formed in step (c) into a housing so that the device is engaged in the housing and abuts the rear surface of the ferrule to hold the ferrule in position in the housing.

9. A method as claimed in claim 8 further comprising the step of securing the jacket of the cable, a reinforcement of the cable or both to the rear end of the device.

10. A method as claimed in claim 8 wherein said step of placing the subassembly includes advancing the subassembly forwardly to engage features of the device and housing and thereby lock the device to the housing.