Optical connector and method for connecting optical connector

1. An optical connector comprising:

an optical receptacle; and

an optical plug that is attachable to and detachable from the optical receptacle, wherein

the optical receptacle includes receptacle-side connector modules that each include:

an outer housing;

an inner housing;

a receptacle-side ferrule housed in the inner housing; and

a receptacle-side spring that applies pressure to the receptacle-side ferrule,

the optical plug includes plug-side connector modules that each include:

a plug-side housing;

a plug-side ferrule housed in the plug-side housing; and

a plug-side spring that applies pressure to the plug-side ferrule,

the inner housing includes an engagement section,

the plug-side housing includes an engaged section,

in a state where the engagement section engages with the engaged section, the inner housing and the plug-side housing have a predetermined positional relationship and the receptacle-side ferrule and the plug-side ferrule abut against each other with predetermined pressure by the receptacle-side spring and the plug-side spring,

the plug-side housing includes an unlocking section,

when the unlocking section causes a locked state where the inner housing is locked by the outer housing to shift to an unlocked state, the inner housing is movable with respect to the outer housing, and

when the optical receptacle and the optical plug are attached to one another and in a state where the engagement section engages with the engaged section after the locked state shifts to the unlocked state in each of a receptacle-side connector module and a plug-side connector module, the inner housing and the plug-side housing move in an attaching or detaching direction with respect to the outer housing,

the optical receptacle includes a receptacle-side cylindrical part with a screw disposed on an outer surface,

the optical plug includes a nut part into which the receptacle-side cylindrical part is screwed,

to shift from the unlocked state to the locked state a screwing of the receptacle-side cylindrical part into the nut part is loosened so that the engagement section is released from the engaged section.

2. The optical connector according to claim 1 , wherein

the locked state shifts to the unlocked state by advancing the screwing of the receptacle-side cylindrical part into the nut part.

3. The optical connector according to claim 2 , wherein the optical plug further includes a plug-side cylindrical part that fits into the receptacle-side cylindrical part.

4. The optical connector according to claim 1 , wherein

the optical receptacle further includes a casing that holds the outer housing, and

the outer housing is movable in a direction perpendicular to an attaching and detaching direction with respect to the casing.

5. The optical connector according to claim 1 , wherein the receptacle-side ferrule and the plug-side ferrule are a lens coupling-type ferrule.

6. The optical connector according to claim 1 , wherein

the optical plug further includes:

a plug-side cylindrical part that is housed in and fits into the receptacle-side cylindrical part during connection to the optical receptacle, and

a ring-shaped operation section that is rotatably disposed on an outer surface of the plug-side cylindrical part and that is screw-fixed to the receptacle-side cylindrical part by a screw disposed on an inner surface.

7. The optical connector according to claim 6 , wherein

an inside of the receptacle-side cylindrical part includes a first key projection that protrudes along an attaching and detaching direction and a first key recess having a groove shape along the attaching and detaching direction, and

an outside of the plug-side cylindrical part includes:

a second key recess that matches the first key projection and has a groove shape along the attaching and detaching direction, and

a second key projection that matches the first key recess and that protrudes along the attaching and detaching direction.

8. The optical connector according to claim 7 , wherein the first key projection is positioned facing the first key recess.

9. The optical connector according to claim 7 , wherein

the first key recess is on a first flat part of a part of the inside of the receptacle-side cylindrical part, and

the second key projection is on a second flat part of a part of the plug-side cylindrical part.

10. The optical connector according to claim 6 , wherein

the optical receptacle further includes a casing that includes a grip and an optical fiber holding part,

the outer housing includes a pair of flange parts, and

the grip and the optical fiber holding part hold the outer housing in the casing to sandwich the pair of flange parts.

11. The optical connector according to claim 10 , wherein the grip and the ring-shaped operation section include a hexagonal-prism-shaped outer surface.

12. A method for connecting an optical connector including an optical receptacle and an optical plug that are attachable to and detachable from one another, wherein the optical receptacle includes receptacle-side connector modules that each includes: an outer housing; an inner housing; a receptacle-side ferrule housed in the inner housing; and a receptacle-side spring that applies pressure to the receptacle-side ferrule, the optical plug includes plug-side connector modules that includes: a plug-side housing; a plug-side ferrule housed in the plug-side housing; and a plug-side spring that applies pressure to the plug-side ferrule, the inner housing includes an engagement section, the plug-side housing includes an engaged section, in a state where the engagement section engages with the engaged section, the inner housing and the plug-side housing have a predetermined positional relationship and the receptacle-side ferrule and the plug-side ferrule abut against each other with predetermined pressure by the receptacle-side spring and the plug-side spring, and the plug-side housing includes an unlocking section, the method comprising:

attaching the optical plug to the optical receptacle;

detaching the optical plug from the optical receptacle;

moving the inner housing with respect to the outer housing by shifting a locked state where the inner housing is locked by the outer housing to an unlocked state using the unlocking section; and

when the optical receptacle and the optical plug are attached to one another and in a state where the engagement section engages with the engaged section after shifting the locked state to the unlocked state in each of receptacle-side connector modules and the plug-side connector modules, moving the inner housing and the plug-side housing an attaching and detaching direction with respect to the outer housing, wherein

the optical receptacle includes a receptacle-side cylindrical part with a screw disposed on an outer surface,

the optical plug includes a nut part into which the receptacle-side cylindrical part is screwed, and

to shift from the unlocked state to the locked state a screwing of the receptacle-side cylindrical part into the nut part is loosened so that the engagement section is released from the engaged section.