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Title:
ADAPTER HOLDER MODULE
Document Type and Number:
WIPO Patent Application WO/2011/094944
Kind Code:
A1
Abstract:
An adapter holder module, comprising: a housing including at least one adapter holder, each adapter holder including a first wall, a second wall opposite to the first wall, a third wall and a fourth wall opposite to the third wall, which cooperatively define an opening for receiving one of a SC-type adapter and a FC-type adapter; wherein each adapter holder further includes a pair of cut-outs respectively formed on an edge of the first wall and an edge of the second wall, and a pair of side openings respectively through the first wall and the second wall, the pair of cut-outs configured to stop a pair of tabs of a SC-adapter inserted into the opening, the pair of side openings configured to receive a pair of retaining clips of the SC-type adapter with a snap-fit mounting, the pair of cut-outs and the pair of side openings cooperatively holding the SC-adapter in place; each adapter holder further including a latching tab located on the inner surface of one of the first wall, the second wall, the third wall and the fourth wall, and a latching stop located on one of the first wall, the second wall, the third wall and the fourth wall, the latching tab and the latching stop configured to capture the flange of a FC-type adapter inserted into the opening.

Inventors:
WEI JIAQIANG (CN)
Application Number:
PCT/CN2010/070536
Publication Date:
August 11, 2011
Filing Date:
February 05, 2010
Export Citation:
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Assignee:
CENTURY MAN COMM CO LTD (CN)
WEI JIAQIANG (CN)
International Classes:
G02B6/38
Domestic Patent References:
WO2005006046A22005-01-20
Foreign References:
US6508593B12003-01-21
US20080050070A12008-02-28
Attorney, Agent or Firm:
KING & WOOD PRC LAWYERS (Office Tower A Jianwai SOHO,,39 Dongsanhuan Zhonglu, Chaoyang District, Beijing 2, CN)
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Claims:
What is claimed

1. An adapter holder module, comprising:

a housing including at least one adapter holder, each adapter holder including a first wall, a second wall opposite to the first wall, a third wall and a fourth wall opposite to the third wall, which cooperatively define an opening for receiving one of a SC-type adapter and a FC-type adapter;

wherein the adapter holder further includes a pair of cut-outs respectively formed on an edge of the first wall and an edge of the second wall, and a pair of side openings respectively through the first wall and the second wall, the pair of cut-outs configured to stop a pair of tabs of a SC-adapter inserted into the opening, the pair of side openings configured to receive a pair of retaining clips of the SC-type adapter with a snap-fit mounting, the pair of cut-outs and the pair of side openings cooperatively holding the SC-adapter in place;

the adapter holder further including a latching tab located on the inner surface of one of the first wall, the second wall, the third wall and the fourth wall, and a latching stop located on one of the first wall, the second wall, the third wall and the fourth wall, the latching tab and the latching stop configured to capture the flange of a FC-type adapter inserted into the opening.

2. An adapter holder module according to claim 1, wherein the adapter holder includes four latching tabs, two of which are located on the inner surface of the first wall and the other two of which are located on the inner surface of the second wall.

3. An adapter holder module according to claim 2, wherein each latching tab is adjacent to a corner formed by two meeting walls among the first wall, the second wall, the third wall and the fourth wall.

4. An adapter holder module according to claim 1, wherein the adapter holder includes two latching stops, respectively located on the inner surfaces of the third and the fourth walls.

5. An adapter holder module according to claim 1, comprising:

a plurality of adapter holders arranged in parallel, the fourth wall of each adapter holder defining a third wall of an adjacent adapter holder.

6. An adapter holder module according to claim 1, further comprising: a fixture for the housing being movably mounted thereon, wherein the housing is movable relative to the fixture between a first position and a second position.

7. An adapter holder module according to claim 6, wherein the housing and the fixture include an intermating structure for providing a sliding movement of the housing relative to the fixture.

8. An adapter holder module according to claim 6, wherein the housing and the fixture further include a positioning structure for positioning the housing at the first position.

9. An adapter holder module according to claim 8, wherein the positioning structure includes two protrusions respectively located on two sides of the housing and two first recesses located on the fixture for mating with the two protrusions respectively.

10. An adapter holder module according to claim 6, wherein the housing and the fixture include a locking structure for interlocking the housing with the fixture at the second position for preventing the housing from moving relative to the fixture.

11. An adapter holder module according to claim 10, wherein the locking structure includes two protrusions respectively located on two sides of the housing and two second recesses located on the fixture, each of the two protrusions including a recessed portion and each of the two second recesses including a locking tab for interlocking with the recessed portion when the housing is at the second position.

Description:
ADAPTER HOLDER MODULE

Technical field

The present invention relates to fiber optic telecommunications equipment. More specifically, the present invention relates to an adapter holder module.

Background of the invention

Fiber optics have revolutionized communication throughout the world. Fiber optics are generally thin strings of glass designed to carry light which can be grouped together. With the increased use 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. Currently, there are various connectors and adapters, but conventional adapter holder only can receive one type of adapter. If a fiber optic equipment is designed to accommodate two types of adapters, the corresponding two types of adapter holders have to be installed on the fiber optic equipment, which leads to cumbersome of the fiber optic equipment.

Summary of the invention

If the type of an adapter connecting two connectors secured in an adapter holder is changed, the adapter holder, even the whole fiber optic equipment, has to be replaced accordingly to be compatible with the type of the adapter.

The present invention proposes an adapter holder which can receive two types of adapters, SC-type adapter and FC-type adapter.

According to one embodiment of the present invention, there is provided an adapter holder module, comprising: a housing including at least one adapter holder, each adapter holder including a first wall, a second wall opposite to the first wall, a third wall and a fourth wall opposite to the third wall, which cooperatively define an opening for receiving one of a SC-type adapter and a FC-type adapter; wherein each adapter holder further includes a pair of cut-outs respectively formed on an edge of the first wall and an edge of the second wall, and a pair of side openings respectively through the first wall and the second wall, the pair of cut-outs configured to stop a pair of tabs of a SC-adapter inserted into the opening, the pair of side openings configured to receive a pair of retaining clips of the SC-type adapter with a snap-fit mounting, and the pair of cut-outs and the pair of side openings cooperatively holding the SC-adapter in place; each adapter holder further including a latching tab located on the inner surface of one of the first wall, the second wall, the third wall and the fourth wall, and a latching stop located on one of the first wall, the second wall, the third wall and the fourth wall, the latching tab and the latching stop configured to capture the flange of a FC-type adapter inserted into the opening.

With the adapter holder module provided in the present invention, each adapter holder can receive two types of adapters, which provides compatibility and high density of fiber optic equipments and systems.

Brief description of the drawings

The above and other objects, characteristics and merits of the present invention will become more apparent from the following detailed description considered in connection with the accompanying drawings, in which:

FIG. 1 illustrates a front perspective view of an adapter holder module according to one embodiment of the present invention;

FIG. 2 illustrates a rear perspective view of the adapter holder module shown in FIG. 1 ;

FIG. 3 illustrates a front view of the adapter holder module shown in FIG. 1 ;

FIG. 4 illustrates a rear view of the adapter holder module shown in FIG. 1 ;

FIG. 5 illustrates a right side view of the adapter holder module shown in FIG. 1 ;

FIG 6 illustrates a left side view of the adapter holder module shown in FIG. 1 ;

FIG. 7 illustrates a bottom view of the adapter holder module shown in FIG 1 ;

FIG 8 illustrates a top side view of the adapter holder module shown in FIG 1 ;

FIG. 9 illustrates a front perspective view of a SC-type adapter according to one embodiment of the present invention;

FIG 10 illustrates a rear perspective view of the SC-type adapter shown in FIG. 9;

FIG. 11 illustrates a front view of the SC-type adapter shown in FIG. 9; FIG 12 illustrates a rear view of the SC-type adapter shown in FIG. 9; FIG 13 illustrates a right side view of the SC-type adapter shown in FIG. 9;

FIG. 14 illustrates a left side view of the SC-type adapter shown in FIG.

9;

FIG. 15 illustrates a top view of the SC-type adapter shown in FIG. 9; FIG 16 illustrates a bottom view of the SC-type adapter shown in FIG.

9;

FIG 17 illustrates a front perspective view of the adapter holder module shown in FIG. 1 with SC-type adapters shown in FIG. 9 inserted;

FIG 18 illustrates a left side perspective view of the adapter holder module with SC-type adapters inserted shown in FIG. 17;

FIG 19 illustrates a rear perspective view of the adapter holder module with SC-type adapters inserted shown in FIG. 17; FIG. 20 illustrates a cross-sectional view of the adapter holder module with SC-type adapters inserted shown in FIG. 17, taken along line 20-20 of FIG. 17;

FIG. 21 illustrates a perspective view of a FC-type adapter according to one embodiment of the present invention;

FIG. 22 illustrates a perspective view of a FC-type adapter shown in FIG. 21 with dust caps mounted thereon;

FIG. 23 illustrates a front view of a FC-type adapter shown in FIG. 22;

FIG. 24 illustrates a top view of a FC-type adapter shown in FIG. 22;

FIG. 25 illustrates a rear perspective view of the adapter holder module shown in FIG. 1 with FC-type adapters shown in FIG. 22 inserted;

FIG. 26 illustrates a front perspective view of the adapter holder module with FC-type adapters inserted shown in FIG. 25;

FIG. 27 illustrates a rear view of the adapter holder module with FC-type adapters inserted shown in FIG 25;

FIG. 28 illustrates a front view of the adapter holder module with FC-type adapters inserted shown in FIG. 25;

FIG 29 illustrates a cross-sectional view of the adapter holder module with FC-type adapters inserted shown in FIG. 27, taken along line 30-30 of FIG 27;

FIG 30 illustrates a cross-sectional view of the adapter holder module with FC-type adapters inserted shown in FIG. 28, taken along line 40-40 of FIG. 28;

FIG. 31 illustrates an adapter module with the housing shown in a retracted position;

FIG. 32 illustrates an adapter module with the housing shown in a fully extended position;

FIG. 33 illustrates a front perspective view of a wall of a fixture according to one embodiment of the present invention;

FIG. 34 illustrates a rear perspective view of the wall shown in FIG.

33;

FIG. 35 illustrates a front view of the wall shown in FIG. 33;

FIG. 36 illustrates a rear view of the wall shown in FIG. 33;

FIG. 37 illustrates a right side view of the wall shown in FIG. 33;

FIG. 38 illustrates a left side view of the wall shown in FIG. 33;

FIG. 39 illustrates a top view of the wall shown in FIG. 33;

FIG. 40 illustrates a bottom view of the wall shown in FIG. 33;

FIG. 41 illustrates a cross-sectional view of the adapter holder module shown in FIG. 32, taken along line 50-50 of FIG. 32;

FIG. 42 illustrates an enlarged view of the locking structure 410 shown in FIG. 41 ;

FIG. 43 illustrates an enlarged view of the protrusion 147 and an enlarged view of the second recess 184;

FIG. 44 illustrates an adapter module with the housing shown in an extended position according to another embodiment of the present invention; wherein same or analogous reference numerals are used to represent same or analogous step features/devices (modules) throughout the figures.

Detailed description of the embodiments

Hereinafter, embodiments of the present invention are described in detail with reference to the accompanying drawings.

FIGS. 1 to 8 show an adapter holder module 100 according to one embodiment of the present invention. As shown in FIGS. 1 to 8, the adapter holder module 100 includes a housing 101 including six adapter holders 102. Each adapter holder 102 is configured to receive a SC-type adapter 200 (shown in FIGS. 9 to 16) or a FC-type adapter 300 (shown in FIGS. 21 to 24). In one embodiment, the housing 101 is a one-piece housing.

Referring to FIGS. 1 and 2, each adapter holder 102 includes a first wall 103, a second wall 104 opposite to the first wall 103, a third wall 105 and a fourth wall 106 opposite to the third wall 105, which cooperatively define an opening 107 for receiving the SC-type adapter 200 or the FC-type adapter 300. Each opening 107 defines a longitudinal axis A.

Referring to FIG. 1, which shows a front perspective view of the adapter holder module 100, each adapter holder 102 includes a pair of cut-outs 108, 109 respectively formed on an edge 110 of the first wall 103 and an edge 111 of the second wall 104, and a pair of side openings 112, 113 respectively through the first wall 103 and the second wall 104. The pair of cut-outs 108, 109 is configured to stop a pair of tabs 202, 201 of a SC-adapter 200 inserted into the opening 107 along the longitudinal axis A from a first end 121 to a second end 122 of the opening 107 in FIG. 1. The pair of side openings 112, 113 is configured to receive a pair of retaining clips 204, 203 of the SC-type adapter 200 with a snap-fit mounting. Hence, the pair of cut-outs 108, 109 and the pair of side openings 112, 113 cooperatively hold the SC-adapter 200 in place.

FIGS. 17 to 19 show three perspective views of the adapter holder module 100 with six SC-type adapters 200 inserted. FIG. 20 shows a cross-sectional view of the adapter holder module 100 with SC-type adapters inserted shown in FIG. 17, taken along line 20-20 of FIG. 17. From FIG. 20, it can be seen that the SC-type adapter 200 shown in FIG. 9 and FIG 20 includes an outer housing 211 , an inner housing 212 composed of two halves, a sleeve 213, a pair of retaining clips 203 and 204 and two dust caps 214 mounted thereon. The pair of tabs 201 and 202 is located on the outer housing 211. The pair of retaining clips 203 and 204 is flexible. It is to be understood that the SC-type adapter 200 shown in FIGS. 9 and 20 is for purpose of illustration only. The SC-type adapter 200 can be a standard SC-type adapter or with a slight difference from a standard SC-type adapter.

Referring to FIG. 1, during the insertion of the SC-type adapter 200 into the adapter holder 102, firstly, the two retaining clips 204 and 203 are pushed respectively by the portion 114 between the cut-out 108 and the side opening 112 of the first wall 103 and the portion 115 between the cut-out 109 and the side opening 113 of the second wall 104, and flex towards each other. Once the two retaining clips 203 and 204 respectively arrive at the two side openings 112 and 113, they flex back to normal and are respectively received by the two side openings 112 and 113. The two side openings 112 and 113 prevent the SC-type adapter 200 from moving toward the cut-outs 108 and 109.

Referring to FIG. 20, the two tabs 202 and 201 of the SC-type adapter 200 are respectively received by the two cut-outs 108 and 109, hence the two tabs 202 and 201 of the SC-type adapter 200 are respectively stopped by the first wall 103 and the second wall 104. This prevents the SC-type adapter 200 from moving towards the side openings 112 and 113.

Referring to FIG.1, in one embodiment, when the SC-type adapter 200 is in place in the opening 107, the bottom surface 116 of the cut-out 108 abuts against the tab 202 and the upper surface 118 (shown in FIG. 2) of the side opening 112 abuts against the retaining clip 204, the bottom surface 117 of the cut-out 109 abuts against the tab 201 and the upper surface 119 (shown in FIG. 2) of the side opening 113 abuts against the retaining clip 203. Alternatively, the longitudinal length of the portions 114 and 115 along the axis A of the opening 107 can be designed to allow for a certain amount of float along the longitudinal axis A of the opening 107 for the SC-type adapter 200 in the opening 107.

The SC-type adapter 200 can be easily taken out by pressing the retaining clips 203 and 204.

Referring to FIGS. 2 to 4, the adapter holder 102 includes two latching tabs 133, 134 located on the inner surface of the first wall 103, and two latching tabs 131, 132 located on the inner surface of the second wall 104. The latching tab 131 is adjacent to a corner formed by the second wall 104 and the third wall 105. The latching tab 132 is adjacent to a corner formed by the second wall 104 and the fourth wall 106. The latching tab 133 is adjacent to a corner formed by the first wall 103 and the third wall 105. The latching tab 134 is adjacent to a corner formed by the first wall 103 and the fourth wall 106.

The adapter holder 102 includes two latching stops 141, 142 respectively located on the inner surface of the third wall 105 and the fourth wall 106. The latching tabs 131 , 132, 133 and 134, and the latching stops 141 and 142, are configured to capture the flange 301 of a FC-type adapter 300 inserted into the opening 107 along the longitudinal axis A from the second end 122 to the first end 121 of the opening 107.

FIGS. 25 and 26 respectively illustrate a rear and a front perspective view of the adapter holder module 100 with FC-type adapters 300 shown in FIG. 22 inserted. FIG. 29 shows a cross sectional view of the adapter holder module 100 with FC-type adapters 300 inserted, taken along line 30-30 of FIG. 27. FIG. 30 shows a cross sectional view of the adapter holder module 100 with FC-type adapters 300 inserted shown in FIG. 28, taken along line 40-40 of FIG. 28. For simplicity, only one FC-type adapter 300 is illustrated in FIG. 30.

From FIGS. 29 and 30, it can be seen that the FC-type adapter 300 includes a tubular inner coupling flange 311 composed by two halves, a tubular outer coupling flange 312 and a sleeve 313. The FC-type adapter 300 further includes two dust caps 314 mounted thereon. The flange 301 is located on the outside of the tubular outer coupling flange 312. It is to be understood that the FC-type adapter 300 shown in FIG. 22 is for purpose of illustration only. The FC-type adapter 300 can be a standard FC-type adapter or with a slight difference from a standard FC-type adapter.

Referring to FIG. 29, each latching tab includes a ramped surface 135 and a square face 136. During the insertion of the FC-type adapter 300, the ramped surface 135 makes contact against the flange 301 of the FC-type adapter 300 and causes the first wall 103 and the second wall 104 to flex out toward the outside of the opening 107. Once the flange 301 clears the ramped surface 135, the first wall 103 and the second wall 104 flex back to normal and the flange 301 of the FC-type adapter 300 is captured between each latching stop and the square face 136 of each latching tab.

The FC-type adapter 300 can be easily taken out by imposing suitable tensile force on the inner surfaces of the first wall 103 and the second wall 104 at the same time.

It is to be noted that the housing 101 is preferably molded out of materials that are flexible and strong enough to allow for insertion of the FC-type adapters. It is also to be noted that each latching tab is sized that it can hold the flange 301 of the FC-type adapter 300 in place with at least one latch stop, at the same time, it is small enough for easy insertion and taking out of the FC-type adapter 300 within the limit of flexibility of the housing 101.

In one embodiment, each latching tab abuts against the flange 301 of the FC-type adapter 300 and each latching stop abuts against the flange 301 of the FC-type adapter 300. Alternatively, the axial distance from one latching tab to one latching stop along the longitudinal axis A is designed to allow for a certain amount of float along the longitudinal axis A for the FC-adapter 300 in the opening 107.

In one embodiment, both the FC-type adapter 300 and SC-type adapter 200 can be inserted into the opening 107 along the longitudinal axis A from the first end 121 to the second end 122 of the opening 107 by changing the locations of the latching tab and the latching stop.

Although each adapter holder 102 shown in FIGS. 25 to 28 includes four latching tabs and two latching stops, it is to be understood that the number of the latching tabs and latching stops are not limited and the location of the latching tabs and latching stops are not limited, either. In one embodiment, the adapter holder 102 includes only one latching tab and one latching stop, and either of the latching tab and the latching stop can be located on the inner surface on any of the first, the second, the third and the fourth walls 103, 104, 105 and 106. In another embodiment, each adapter 102 includes four latching tabs respectively located on the inner surfaces of the first, the second, the third and the fourth walls.

In FIGS. 1 to 8, the adapter holder module 100 includes six adapter holders 102 and the six adapter holders 102 are arranged in parallel, wherein the fourth wall 106 of each adapter holder 102 defines a third wall 105 of an adjacent adapter holder 102. The first walls 103 of all adapter holders 102 are integrally formed. The second walls 104 of all adapter holders 102 are integrally formed too.

It is to be understood that the number of the adapter holders 102 are not limited and the arrangement of a plurality of adapter holders 102 can be various, not limited to the parallel arrangement shown in FIGS. 1 to 8.

The adapter holder module 100 shown in FIG. 1 can further include a fixture 150 for the housing 101 being movably mounted thereon. The housing 101 is movable along a line of travel that is non-parallel to the longitudinal axes of the openings, i.e. non-parallel to the longitudinal axis A. The housing 101 can be movable relative to the fixture between a first position and a second position. In one embodiment, the first position is a position where the housing 101 is in a retracted position relative to the fixture 150, as shown in FIG. 31 ; and the second position is a position where the housing 101 is in a fully extended position relative to the fixture 150, as shown in FIG. 32.

For easy mounting and withdrawal, the housing 101 can further include a handle 190, as shown in FIGS. 1 and 2.

In FIG. 31 and 32, the fixture 150 includes a bottom panel 160 and two walls 170. Each wall 170 can be mounted to the bottom panel 160 by fasteners, for example by two screws respectively through two fastener holes 161, as shown in FIGS. 31 and 32. It is to be noted that in other embodiments, other types of fastening structures can also be used. The fixture 150 can be mounted to other telecommunication assemblies (not shown in FIG. 31 and 32).

In FIG. 31, the housing 101 is shown in a retracted position, i.e. the first position, relative to the walls 170. In FIG. 32, the housing 101 is shown in a fully extended position, i.e. the second position, relative to the walls 170. The housing 101 and the fixture 150 include an intermating structure for providing the sliding movement of the housing 101 relative to the fixture 150. In one embodiment, the intermating structure includes a pair of guiding rails 144 and 145 (shown in FIG. 2) respectively located on two sides of the housing 101 and two tracks 171 and 172 formed by two grooves respectively on two adjacent walls 170 (shown in FIG. 32).

The housing 101 and the fixture 150 include a positioning structure for positioning the housing at the first position, i.e. the retracted position shown in FIG. 31. In one embodiment, the positioning structure includes two protrusions 146 and 147 respectively located on two sides of the housing 101, as shown in FIGS. 1 and 2, and two first recesses 181 and 182 on the fixture 150 for mating with the two protrusions 146 and 147 respectively, as shown in FIG. 32.

During the insertion of the housing 101 into the fixture 150, the two walls 170 are pushed by the two protrusions 146 and 147 and flex out. When the two protrusions 146 and 147 respectively arrive at the location of the two first recesses 181 and 182, they are received by the two first recesses 181 and 182 and the two walls 170 flex back. It is also to be noted that in this case the walls 170 are preferably molded out of materials that are flexible and strong enough to allow for insertion of the housing 101.

Alternatively, in the case that the walls 170 are almost inflexible, during the insertion of the housing 101 into the fixture 150, the two protrusions 146 and 147 are pushed by the two walls 170, which causes the first wall 103 and the second wall 104 flex toward each other. When the two protrusions 146 and 147 respectively arrive at the locations of the two first recesses 181 and 182, the first wall 103 and the second wall 104 flex back and the two protrusions 146 and 147 are received by the two first recesses 181 and 182.

Alternatively, in some situations, during the insertion of the housing 101 into the fixture 150, not only the two walls 170 flex out but also the first wall 103 and the second wall 104 flex toward each other. When the two protrusions 146 and 147 are received by the two first recesses 181 and 182, the two walls 170, the first wall 103 and the second wall 104 flex back to normal.

It is to be noted that the positioning structure shown in FIGS. 31 and 32 are for purpose of illustration only, other types of positioning structure can also be applied.

The housing 101 and the fixture 150 further include a locking structure for interlocking the housing 101 with the fixture 150 at the second position, i.e. the fully extended position shown in FIG. 32, for preventing the housing 101 from moving relative to the fixture 150.

In one embodiment, the locking structure includes two protrusions 146 and 147 (referring to FIGS. 1 and 2) respectively located on two sides of the housing and two second recesses 183 and 184 located on the fixture 150. Two recessed portions 148 and 149 are respectively on the two protrusions 146 and 147. The second recess 183 includes a locking tab 185 and the second recess 184 includes a locking tab 186. The two locking tabs 185, 186 interlock respectively with the recessed portions 148 and 149 of the two protrusions 146 and 147 when the housing 101 is at the second position, as shown in FIGS. 41 and 42.

FIG. 43 shows an enlarged view of the protrusion 147 and an enlarged view of the second recess 184, the face 139 of the recessed portion 149 abuts against the face 187 of the locking tab 186 and prevents the housing 101 from moving relative to the fixture 150.

It is to be noted that the locking structure shown in FIGS. 31 and FIG. 32 are for purpose of illustration only, other types of locking structure can also be applied. It is also to be noted is that the adapter holder module shown in FIG. 31 and FIG. 32 can have merely the locking structure or merely the positioning structure.

For simplicity, only two walls 170 are shown in FIGS. 31 and 32. In one embodiment, the fixture 150 can include a plurality of walls 170 and each pair of two adjacent walls 170 can receive one housing 101, as shown in FIG. 44. It is to be noted that the structure of the fixture 150 shown in FIGS. 31 and 32 is for purpose of illustration only, the structure of the fixture 150 can be of various types and not limited to the embodiment shown in FIGS. 31 and 32. For example, the bottom panel 160 and the plurality of walls 170 can be integrally form as one-piece fixture.

It should be noted that the above-described embodiments is for purpose of illustration only and not to be construed as limitation of the invention. All such modifications which do not depart from the spirit of the invention are intended to be included within the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word "comprising" does not exclude the presence of elements or steps not listed in a claim or in the description. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. In the apparatus claims enumerating several units, several of these units can be embodied by one and the same item of hardware or software. The usage of the words first, second and third, et cetera, does not indicate any ordering. These words are to be interpreted as names.