JP2012037617A - Optical module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical module capable of certainly holding and fixing an upper housing and a lower housing, while reducing a number of parts and assembling man-hour.SOLUTION: An optical module 1 comprises a lower housing 2 having an element storage wall portion 5, and an upper housing 3 rotatably attached on the lower housing 2. A locking protrusion 19 is protrusively provided on a back surface of the upper housing 3, and a claw portion 20 is provided at a tip end portion of the locking protrusion 19. In a member storage recessed portion of the element storage wall portion 5, a magnetic shield member 21 is fitted. At an upper center of the magnetic shield member 21, a U-shaped plate spring portion 25 for locking the lower housing 2 and the upper housing 3 is provided. The plate spring portion 25 engages with the claw portion 20 of the locking protrusion 19. Concretely, when the upper housing 3 closes to the lower housing 2, while a tip end of the plate spring portion 25 abuts on a receiving surface of the claw portion 20, the claw portion 20 elastically deforms the plate spring portion 25 against energizing force.

Description

  The present invention relates to an optical module having optical elements such as a light emitting element and a light receiving element.

  As a conventional optical module, for example, as described in Patent Document 1, a lower housing that houses a light emitting element, a light receiving element, and an electric circuit board, and an upper housing that covers the inside of the lower housing are provided. What you have is known.

International publication: WO03 / 071327

  However, the following problems exist in the prior art. That is, when the upper housing is closed with respect to the lower housing, if there is rattling between the lower housing and the upper housing, it is difficult to effectively suppress EMI noise generated in the module. Become. For this reason, the lower casing and the upper casing are screwed to eliminate rattling between the lower casing and the upper casing. However, in this case, the number of parts increases, or the cost increases due to the addition of a tapping process and the number of assembly steps increases.

  The objective of this invention is providing the optical module which can hold | maintain and fix a lower housing | casing and an upper housing | casing reliably, aiming at reduction of a number of parts and an assembly man-hour.

  An optical module of the present invention includes a lower housing having an element housing portion for housing an optical element, an upper housing that is rotatably attached to the lower housing and covers an area including the element housing portion, and an element housing portion. An auxiliary member that is mounted; and a locking means that locks the lower housing and the upper housing. The locking means includes a locking elastic portion provided on the upper portion of the auxiliary member, and an upper housing. It is provided and has the latching protrusion which engages with the elastic part for latching, It is characterized by the above-mentioned.

  In such an optical module of the present invention, when the upper casing is rotated and closed with respect to the lower casing, the locking projection provided on the upper casing is held in the auxiliary casing. The lower casing and the upper casing are locked by elastically deforming the locking elastic portion provided at the upper portion of the member against the urging force. At this time, since the locking projection is pressed against the lower housing by the urging force of the locking elastic portion, rattling between the lower housing and the upper housing is suppressed. Further, in order to eliminate rattling (gap) between the lower housing and the upper housing, the lower housing and the upper housing need not be fixed with screws. As described above, the lower housing and the upper housing can be securely held and fixed while reducing the number of parts and the number of assembly steps of the optical module.

  Preferably, there is further provided a fixing member that sandwiches and fixes the lower casing and the upper casing together in a state where the lower casing and the upper casing are locked by the locking means. In this case, the lower housing and the upper housing can be more securely held and fixed by the fixing member.

  Preferably, the locking elastic portion has a leaf spring structure bent in a U-shape, and a claw portion for receiving the tip of the locking elastic portion is provided at the tip of the locking protrusion. ing. In this case, rattling between the lower housing and the upper housing can be suppressed while simplifying the structure of the locking means.

  Further, preferably, the element accommodating portion is provided with a wall for positioning the optical element with respect to the front-rear direction of the lower housing, and the auxiliary member has a flange provided on the optical element as a wall. A plurality of pressing elastic portions to be pressed are provided. In this case, it is not necessary to prepare a separate component for pressing the flange portion provided on the optical element against the wall, so that the number of components of the optical module can be further reduced.

  Preferably, the lower casing has a pair of side walls disposed on the left and right sides of the lower casing, and the upper surface of the rear end of each side wall is lowered toward the rear side of the lower casing. The inner surface of the rear end portion of each side wall is provided with a semicircular cross-section convex part for the rotating shaft, and the upper surface of the rear end portion of the upper housing is arranged on the rear side of each side wall. It is flush with the upper surface of the end portion, and on both side surfaces of the rear end portion of the upper casing, a concave portion for the rotary shaft having a semicircular cross section that fits with the convex portion for the rotary shaft is provided. The upper surface of the rear end portion of each side wall in the lower housing is inclined so as to descend toward the rear side of the lower housing, and the upper surface of the rear end portion of the upper housing is flush with the upper surface of the rear end portion of each side wall. In other words, the inclined surface makes it easier to insert the optical module into the cage, for example, when the optical module is connected to a host connector covered with the cage. In addition, a semicircular rotating shaft convex portion is provided on the inner side surface of each side wall of the lower housing, and a semicircular sectional shape is fitted on both side surfaces of the rear end portion of the upper housing with the rotating shaft convex portion. By providing the concave portion for the rotating shaft, for example, when the optical module is inserted into the cage, the connection terminals arranged in the cage are not easily caught by the rear end portion of the upper housing.

  Further preferably, an area for accommodating an electric circuit board physically connected to the optical element is provided on the rear side of the element accommodating portion in the lower housing, and the auxiliary member is generated by the electric circuit board. It has a function to shield electromagnetic noise. In this case, it is not necessary to separately prepare a member for shielding electromagnetic noise generated in the electric circuit board, so that the number of parts of the optical module can be further reduced.

  According to the present invention, it is possible to securely hold and fix the lower housing and the upper housing while reducing the number of parts and the number of assembly steps, and to improve the effect of suppressing EMI noise.

It is a perspective view which shows a part of one Embodiment of the optical module concerning this invention. It is a disassembled perspective view of a lower housing | casing and an upper housing | casing. It is a perspective view which shows the state in which the optical element and the electric circuit board | substrate were accommodated in the lower housing | casing. It is a perspective view when an upper housing | casing is seen from the back side. It is a fragmentary perspective view which shows the state by which the electromagnetic shielding member was mounted | worn with the lower housing | casing. It is a perspective view which shows the external appearance of an electromagnetic shielding member. It is sectional drawing which shows the state in which the optical element was accommodated in the lower housing | casing. It is sectional drawing which shows a state when an upper housing | casing is closed with respect to a lower housing | casing. It is a perspective view which shows the state by which the fixing member was mounted | worn with the lower housing | casing and the upper housing | casing. It is a perspective view which shows the external appearance of a fixing member. It is a perspective view when an optical module is seen from another angle.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of an optical module according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a perspective view showing a part of an embodiment of an optical module according to the present invention. In the figure, the optical module 1 of the present embodiment includes a lower housing 2 and an upper housing 3 rotatably attached to the lower housing 2. The lower housing 2 and the upper housing 3 are, for example, aluminum die cast products.

  As shown in FIGS. 1 and 2, the lower housing 2 is provided on a receptacle wall 4 having two receptacles 4 a into which optical connectors (not shown) are inserted, and on the rear side of the receptacle wall 4. And an element housing wall 5.

  As shown in FIG. 3, two optical elements (light emitting element and light receiving element) 6 are accommodated side by side in a region including the element accommodating wall 5 in the lower housing 2. In addition, an electrical circuit board 7 physically connected to each optical element 6 is accommodated in a region behind each optical element 6 in the lower housing 2. Electronic components such as a driving IC for driving the optical element 6 are mounted on the electric circuit board 7.

  The lower housing 2 has a pair of side walls 8 extending rearward from the left and right sides of the receptacle wall 4. The upper surface 8 a of the rear end portion of each side wall 8 is an inclined surface that is lowered toward the rear side of the lower housing 2. A rotary shaft convex portion 9 having a semicircular cross section is provided at the rear upper end of the inner surface of each side wall 8.

  The element housing wall 5 includes a front wall 10 having two insertion holes 10a communicating with each receptacle 4a, and a rear wall 11 provided on the rear side of the front wall 10 and having a height lower than that of the front wall 10. Have. Between the front wall 10 and the rear wall 11 in the element housing wall 5, a member housing recess 12 for mounting an electromagnetic shield member 21 (see FIG. 5) described later is formed.

  A cutout 13 having a rectangular cross section is formed at the center upper end of the front wall 10. Grooves 14 extending in the front-rear direction of the lower housing 2 are formed on the left and right sides of the respective insertion holes 10a in the upper portion of the front wall 10. The rear wall 11 is a wall for positioning the optical element 6 with respect to the front-rear direction of the lower housing 2. Two curved concave portions 15 are formed in the rear wall 11 side by side in the width direction of the lower housing 2.

  The upper housing 3 is connected to the rotation shaft projections 9 provided at the rear end portion of the lower housing 2 so as to cover the area in the lower housing 2 that accommodates the optical elements 6 and the electric circuit board 7. And is pivotally attached. The upper surface 3 a of the rear end portion of the upper housing 3 is an inclined surface that is lowered toward the rear side of the upper housing 3. When the upper housing 3 is closed with respect to the lower housing 2, the upper surface 3 a of the rear end portion of the upper housing 3 is flush with the upper surface 8 a of the rear end portion of each side wall 8. At the rear upper ends of both side surfaces of the upper housing 3, there are formed rotational shaft concave portions 16 having a semicircular cross section that fit into the respective rotational shaft convex portions 9 of the lower housing 2.

  As shown in FIG. 4, a protruding wall 17 protrudes from the front side portion of the back surface of the upper housing 3. On the protruding wall 17, two curved concave portions 18 are formed side by side in the width direction of the upper housing 3. The curved concave portion 18 forms a circular insertion hole through which the optical element 6 is inserted in cooperation with the curved concave portion 15 formed in the rear wall 11. On the front side of the projecting wall 17 on the back surface of the upper housing 3, a locking projection 19 is projected. A claw portion 20 is provided at the distal end portion of the locking projection 19.

  As shown in FIGS. 3 and 5, the member housing recess 12 formed in the element housing wall 5 of the lower housing 2 has an electromagnetic wave made of a sheet metal part made of, for example, an iron alloy, an aluminum alloy, or a copper alloy. A shield member 21 is inserted. The electromagnetic shield member 21 is a member that shields noise generated in the electric circuit board 7 so as not to leak outside.

  As shown in FIG. 6, two left and right hook pieces 22 that engage with the groove portion 14 formed on the front wall 10 of the element housing wall portion 5 are provided on the upper portion of the electromagnetic shield member 21. By inserting these hooking pieces 22 into the groove portion 14 as shown in FIG. 5, even if the electromagnetic shielding member 21 tries to come out of the member receiving recess 12, each hooking piece 22 is hooked on the front wall 10. Does not escape from the member receiving recess 12.

  The electromagnetic shield member 21 has two insertion holes 23 through which the optical element 6 is inserted. Three flat plate spring portions 24 for positioning the optical element 6 with respect to the front-rear direction of the lower housing 2 are provided around each insertion hole 23 in the electromagnetic shield member 21. As shown in FIG. 7, these leaf spring portions 24 press the flange portion 6 a provided on the optical element 6 against the rear wall 11 with an urging force (spring force), thereby causing the optical element 6 to be attached to the lower housing 2. Align with the front-rear direction.

  A U-shaped leaf spring portion 25 for locking the lower housing 2 and the upper housing 3 is provided at the upper center of the electromagnetic shield member 21. The leaf spring portion 25 is bent in a U shape with respect to the upper side of the electromagnetic shield member 21. As shown in FIG. 8, the leaf spring portion 25 engages with the claw portion 20 of the locking projection 19 provided on the upper housing 3.

  Specifically, when the upper housing 3 is closed with respect to the lower housing 2, the locking protrusion 19 enters the notch 13 of the front wall 10, and the tip of the leaf spring portion 25 is brought into contact with the receiving surface of the claw portion 20. In the contacted state, the claw portion 20 elastically deforms the leaf spring portion 25 against the urging force. Note that the receiving surface of the claw portion 20 is inclined at a predetermined angle (for example, 45 degrees) with respect to the extending direction of the locking projection 19.

  At this time, the locking projection 19 is pressed against the front wall 10 by the urging force of the leaf spring portion 25. For this reason, the lower casing 2 and the upper casing 3 are locked without rattling.

  Further, as shown in FIG. 9, the optical module 1 has a substantially rectangular cross section in which the lower housing 2 and the upper housing 3 are sandwiched and fixed together while the upper housing 3 is closed with respect to the lower housing 2. A fixing member 26 having a shape is further provided. The fixing member 26 is made of a sheet metal part made of, for example, an iron alloy, an aluminum alloy, a copper alloy, or the like. The fixing member 26 is provided with a plurality of finger portions 26a arranged in a tooth shape.

  As shown in FIG. 10, two circular through holes 27 are formed on the upper surface portion of the fixing member 26. At the center of the lower surface portion of the fixing member 26, a bent protrusion 28 is provided which is bent from the left and right sides toward the upper surface portion.

  On the upper surface of the upper housing 3, as shown in FIG. 1 and the like, two circular protrusions 29 that fit into the through holes 27 of the fixing member 26 are provided. As shown in FIG. 11, a recess 30 is formed on the bottom surface of the lower housing 2 so as to be fitted with the bending protrusion 28 of the fixing member 26. When the fixing member 26 is attached to the lower housing 2 and the upper housing 3, the protrusions 29 of the upper housing 3 are fitted in the through holes 27 of the fixing member 26 as shown in FIG. 26 bent protrusions 28 are inserted into the recesses 30 of the lower housing 2.

  The optical module 1 configured as described above is connected to a host connector (not shown) on the board. The host connector is covered with a housing gauge. When the optical module 1 is connected to the host connector, the optical module 1 is inserted into the housing gauge. At this time, the upper surface 8a of the rear end portion of the lower housing 2 and the upper surface 3a of the rear end portion of the upper housing 3 are both inclined surfaces that are lowered toward the rear side. For this reason, the optical module 1 can be smoothly inserted into the housing gauge without being caught on the housing gauge.

  A spring-like connection terminal for electrical connection is arranged in the housing gauge. Here, the rear upper end of the lower housing 2 is provided with a semicircular rotary shaft convex portion 9, and the upper upper portion of the upper housing 3 is fitted with the rotary shaft convex portion 9. A rotary shaft recess 16 having a semicircular cross section is formed. That is, there is no deep gap in the rotary shaft recess 16. For this reason, when the optical module 1 is inserted into the housing gauge, the connection terminals are not easily caught by the upper housing 3. Further, since the fixing member 26 is provided with a plurality of finger portions 26a, the electrical connection between the connection terminal and the housings 2 and 3 is reliably performed through the finger portions 26a.

  As described above, in the present embodiment, the U-shaped leaf spring portion 25 is provided on the upper portion of the electromagnetic shield member 21 attached to the lower housing 2, and the leaf spring portion 25 is provided on the back surface of the upper housing 3. By providing the locking projection 19 having the claw portion 20 that receives the tip of the upper housing 3, the upper housing 3 is locked to the lower housing 2 using the elastic deformation of the leaf spring portion 25. The backlash between the body 2 and the upper housing 3 is suppressed. Thereby, the lower housing 2 and the upper housing 3 can be reliably held and fixed. Further, in order to eliminate rattling (gap) between the lower casing 2 and the upper casing 3, the lower casing 2 and the upper casing 3 are fixed with screws, or the lower casing 2 and the upper casing 3 There is no need to interpose a flexible sheet or gel. Therefore, the number of parts of the optical module can be reduced. As a result, cost reduction and assembly man-hours can be reduced.

  In addition, since the fixing member 26 that sandwiches and fixes the lower housing 2 and the upper housing 3 together is provided, the locked state between the lower housing 2 and the upper housing 3 is temporarily released for some reason. In addition, the holding and fixing state of the lower housing 2 and the upper housing 3 can be maintained.

  As described above, since both are held and fixed so as to eliminate the gap between the lower housing 2 and the upper housing 3, the effect of suppressing the EMI noise of the optical module 1 can be improved.

  The electromagnetic shield member 21 has a leaf spring portion 25 for locking the upper housing 3 to the lower housing 2 and a plurality of plates for positioning the optical element 6 in the front-rear direction of the lower housing 2. Since the spring portion 24 is provided, it is not necessary to prepare another member having these leaf spring portions. Therefore, since it is not necessary to increase the number of parts of the optical module 1, further cost reduction can be achieved.

  The present invention is not limited to the above embodiment. For example, in the above embodiment, the electromagnetic shield member 21 is provided with the leaf spring portion 25 for locking the upper housing 3 to the lower housing 2 and the optical element 6 for positioning in the front-rear direction of the lower housing 2. However, the present invention is not limited to such a configuration, and the member having the leaf spring portion 25 and the plurality of leaf spring portions 24 shields noise generated in the electric circuit board 7. You may make it provide separately from a member.

DESCRIPTION OF SYMBOLS 1 ... Optical module, 2 ... Lower housing | casing, 3 ... Upper housing | casing, 3a ... Upper surface (inclined surface), 5 ... Element accommodating wall part (element accommodating part), 6 ... Optical element, 6a ... Flange part, 7 ... Electricity Circuit board, 8 ... sidewall, 8a ... upper surface (inclined surface), 9 ... rotating shaft projection, 11 ... rear wall, 16 ... rotating shaft recess, 19 ... locking projection (locking means), 20 ... claw , 21... Electromagnetic shield member (auxiliary member), 24... Leaf spring part (pressing elastic part), 25... Leaf spring part (locking elastic part, locking means), 26.

Claims (6)

A lower housing having an element accommodating portion for accommodating an optical element;
An upper housing that is rotatably attached to the lower housing and covers an area including the element housing portion;
An auxiliary member attached to the element accommodating portion;
A locking means for locking the lower housing and the upper housing;
The locking means includes a locking elastic portion provided on an upper portion of the auxiliary member, and a locking protrusion provided on the upper housing and engaged with the locking elastic portion. And optical module.   The fixing device further includes a fixing member that sandwiches and fixes the lower casing and the upper casing together in a state where the lower casing and the upper casing are locked by the locking means. Item 5. The optical module according to Item 1. The locking elastic portion has a leaf spring structure bent in a U shape,
The optical module according to claim 1, wherein a claw portion that receives a distal end of the locking elastic portion is provided at a distal end portion of the locking protrusion. The element accommodating portion is provided with a wall for positioning the optical element with respect to the front-rear direction of the lower housing,
The optical module according to claim 1, wherein the auxiliary member is provided with a plurality of pressing elastic portions that press a flange portion provided in the optical element against the wall. . The lower housing has a pair of side walls disposed on the left and right sides of the lower housing,
The upper surface of the rear end portion of each side wall is an inclined surface that falls toward the rear side of the lower housing,
On the inner side surface of the rear end portion of each side wall, a convex part for a rotating shaft having a semicircular cross section is provided,
The upper surface of the rear end portion of the upper casing is flush with the upper surface of the rear end portion of each side wall,
5. The rotating shaft recess having a semicircular cross section that fits with the rotating shaft protrusion is provided on both side surfaces of the rear end portion of the upper casing. An optical module according to claim 1. On the rear side of the element accommodating portion in the lower housing, a region for accommodating an electric circuit board physically connected to the optical element is provided,
The optical module according to claim 1, wherein the auxiliary member has a function of shielding electromagnetic noise generated in the electric circuit board.

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