One-piece LC type optical fiber adapter

A one-piece LC type optical fiber adapter is provided. The LC type adapter of the present invention has fewer parts than a conventional one. Therefore, it is simpler and easier to assemble the LC type adapter of the present invention. In addition, the main body of the LC type adapter is unitary thereby avoiding the prior art problem that the stresses cause the two halves of the adapter to separate from each other after time.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a fiber adapter, and more particularly, to a one-piece LC type optical fiber adapter.

2. Description of the Related Art

Fiber optics has revolutionized communication through out the world. With the increased used of fiber optics it has become increasingly important to be able to connect and disconnect fiber optic cables from various sources. Two fiber optic cables can be optically coupled so that they are in communication with each other by using connectors and an adapter, thereby putting each fiber optic cable in communication with the other. The connectors are placed on the end of each cable and then plugged into the adapter. The adapter has two openings each one designed to receive a connector.

The conventional LC type adapter consists of two halves, each halve being identical. Each half consists generally of a rectangular cylinder having a flange at one end. Inside each half would be placed half of an inner housing. The inner housing is generally a round cylinder with a flange at one end. Each adapter half has a ridge located just inside from its flange so that the inner housing could be placed in the adapter through the opening proximate to the flange on the adapter half. Once the inner housing is inserted into each adapter half, the two halves are connected by ultrasonically welding the two flanges of the adapter halves together.

However, the above design presents serious problems. The cables are naturally flexed in use when the adapter remains fixed. The related stress of this situation can cause the two halves of the adapter to separate from each other after time. In the prior art, this problem can be solved by constructing the adapter halves from metal which gives the adapter enough strength to withstand these stresses. However, this too presented a problem as metal is much more expensive to purchase and mold than the plastic one.

Accordingly, there exists a need to provide a LC type optical fiber adapter to solve the aforesaid problems.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a one-piece LC type optical fiber adapter that has fewer parts than a conventional one. It is simpler and easier to assemble the LC type adapter of the present invention. In addition, the main body of the LC type adapter is unitary thereby avoiding the prior art problem that the stresses cause the two halves of the adapter to separate from each other after time.

In order to achieve the above object, the one-piece LC type optical fiber adapter of the present invention includes a unitary main body, an inner housing and a cover. The unitary main body has an axial cavity defined by a first side-wall, a second side-wall, a third side-wall and a fourth side-wall. The first side-wall faces the third side-wall and connects with the second and fourth side-walls. The main body has two opposing axial openings. At least one compartment wall is positioned in the axial cavity. The compartment wall is parallel to the second and fourth side-walls and connects with the first and third side-walls and divides the axial cavity into a plurality of parts. The first side-wall has an access opening thereon. An indentation is formed on the top of the compartment wall. A pair of parallel ridges is positioned on the inner surface of the third side-wall and divides the compartment wall into two halves. The two ridges define a first groove. The second side-wall has a second groove on the inner surface thereof and the fourth side-wall has a third groove on the inner surface thereof. The first groove is in communication with the second and third grooves. A plurality of protrusions is located near the two axial openings on the inner surfaces of the second and fourth side-walls and on opposite sides of the compartment wall, respectively. The inner housing has a flange and a plurality of hollow cylinders through the flange. The cover is configured to cover the access opening on the first side-wall, wherein the cover has a protruding portion formed thereon and a protrusion formed on the protruding portion. The protruding portion is positioned corresponding to the indentation on the top of the compartment wall. The axial cavity of the main body is adapted to receive the inner housing and the first, second and third grooves are adapted to receive the flange. The inner housing can be slid into place within the main body through the opening on the first side-wall. The indentation on the top of the compartment wall is configured to receive the protruding portion and molten protrusion on the cover when the protrusion on the cover is melted and the cover is brought to cover the access opening.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring toFIG. 1, a conventional LC type fiber connector100has a generally rectangular shape with a square cross section. The outer surface of the connector100includes a spring latch120. The spring latch120is molded into the outer housing of the connector and includes a living hinge125which allows tab126to be moved up and down in a direction perpendicular to the central axis150-150of the connector100. In addition, a ferrule140protrudes from the opening111of a two-piece assembly comprising housing110and cover130which have been ultrasonically bonded together. A spring (not shown in the figure) is located inside the two-piece assembly to allow the ferrule140to move back and forth through the opening111. The spring latch120includes a pair of shoulders121that are positioned on opposite sides of the tab126.

Referring toFIGS. 2 to 5, the duplex fiber adapter200of the present invention includes a unitary molded main body205and a cover300. In the preferred embodiment, the main body205has an axial cavity defined by top side-wall210, bottom side-wall211, right side-wall212and left side-wall213. The axial cavity is divided into two halves by a compartment wall214that is parallel to the right side-wall212and left side-wall213and connects with the top side-wall210and bottom side-wall211. The half of the axial cavity defined by the top side-wall210, bottom side-wall211, compartment wall214and right side-wall212is named as the right axial cavity and the other half of the axial cavity defined by the top side-wall210, bottom side-wall211, compartment wall214and left side-wall213is named as the left axial cavity. The right axial cavity has opposing first right opening207aand second right opening208aand the left axial cavity has opposing first left opening207band second left opening208b. In addition, an indentation219is formed on the top of the compartment wall214.

Located on the exterior of the main body205is a pair of tabs201and202. One tab202is located on the right side-wall212and the other tab201is located on the left side wall213. The tabs201and202are operative in supporting the adapter200on a surface. The inner cavity of the main body205contains a pair of parallel ridges235and236located on the inner surface of the bottom side-wall211. The ridges235and236are perpendicular to the axial cavity of the main body205and divide the compartment wall214into two halves.

The ridges235and236define a groove238which is perpendicular to the axial cavity of the main body205. The groove238is half way between the first openings207a,207band second openings208a,208bof the main body205. The width of the groove238is equal to the thickness of combined flanges450of the inner housing halves410and420. The right side-wall212and left side-wall213each has a groove239that is collinear with the groove238. Two indentations237are formed on the joint of the tab202with the right side-wall212and on the joint of the tab201with the left side-wall213, respectively. The indentations237are in communication with and collinear with the grooves239.

Located near the right opening207aon the joint of the right side-wall212with the bottom side-wall211and on the joint of the compartment wall214with the bottom side-wall211are protrusions262. The protrusions262are also located near the left opening207bon the joint of the left side-wall213with the bottom side-wall211and on the joint of the compartment wall214with the bottom side-wall211. Similarly, these protrusions262are also located near the openings208a,208bon the joints of the bottom side-wall211with the right side-wall212, compartment wall214and left side-wall213, respectively.

An access opening250is located on the top side-wall210. The access opening250allows inner housing halves410and420to be inserted into the axial cavity of the main body205and also allows the main body205to be constructed by injection molding.

The inner housing halves410and420are identical. Each of the inner housing halves410and420is constructed of plastic by an injection molding process. Each half includes two hollow cylinders440and a rectangular flange450located at one end of the cylinder440. Two halves410and420are connected at their respective flanges450respectively so as to define two common cylinders. Two flanges450define a thickness which is equal to the widths of the groove238and239. The inner housing halves410,420are placed in the main body205by aligning the flange450of the inner housing half410with collinear grooves238and239and sliding it into place within the main body205. The other inner housing half420is inserted into the main body205in the same fashion.

The cylinders440of the inner housing halves410and420are coaxial in the main body205and define two common cylinders. Located in each of the common cylinders is a hollow sleeve500with a generally cylindrical shape. The cover300has a bottom surface320and a rectangular protruding portion330positioned on the bottom surface320, wherein the protruding portion330is arranged corresponding to and can be placed with the indentation219on the compartment wall214. A smaller protrusion332is formed on the protruding portion330. The protrusion332has a rectangular bottom surface and a triangular cross-section. In addition, the cover300further includes a pair of ribs310, which are positioned corresponding to the indentations237on the tabs201,202, respectively (SeeFIG. 5).

When desiring to assemble the fiber adapter200, the inner housing halves410and420are inserted into the axial cavity of the main body205through the access opening250. Afterward, the protrusion332on the cover300is ultrasonically melted and the cover300is brought to cover the access opening250. At this moment the protruding portion330will be placed within the indentation219on the compartment wall214and the molten protrusion332will bond to the compartment wall214so that the cover300can be tightly attached to the main body205. Since the ribs310of the cover300are arranged corresponding to the indentations237on the tabs201and202, the ribs310will be placed within the indentations237when the cover300is brought to cover the access opening250.

In operation the connector100is inserted into the main body205from, for example, the first right opening207a. The shoulders121positioned on the opposite sides of the tab126of the spring latch120are pushed by the protrusions262to cause the spring latch120to be deflected downward during the insertion into the main body205. The ferrule140of the connector100is inserted into one end of the hollow sleeve500in the right axial cavity. When the shoulders121pass over the protrusions262, the spring latch120is then returned to its original position by its own restorative force to have the shoulders121moved upward to position behind the protrusions262. The protrusions262can stop the backward movement of the shoulders121to prevent the connector100from being pulled out from the adapter200. Another connector100can be inserted into the main body205from the second right opening208ain the same manner to have its ferrule140to be inserted into the other end of the sleeve500in the right axial cavity. The end face of the ferrule140will be brought into contact with that of the previous ferrule140. Similarly, two connectors100can be inserted into the main body205from the first left opening207band the second left opening208brespectively to optically couple with each other.

In addition to duplex fiber adapter, the fiber adapter of the present invention can also be designed to couple four pairs of connectors (not shown in the figure). More specifically, the axial cavity in the main body of the adapter is divided into four parts by three parallel compartment walls. Four connectors can be inserted into the front ends of the four parts of the axial cavity respectively in the above-described manner. Similarly, another four connectors can be inserted into the rear ends of the four parts of the axial cavity to couple with the opposite connectors, respectively. Since the structure of this adapter is substantially identical to that of the adapter200, any further illustrations of such adapter are omitted herein.

Since the main body of the fiber adapter according to the present invention is unitary, the prior art problem that the stresses cause the two halves of the adapter to separate from each other after time can be avoided.