Abstract:
A transceiver module has an interface surface and is received within a cage. The cage has a cage latch that retains the transceiver module. The transceiver module has a ramp, an actuator and a release handle. The ramp is located on the interface surface of the transceiver module and has a ramp surface that slopes away from the interface surface of the transceiver module and toward the cage latch. The actuator is adjacent the interface surface of the transceiver module and is configured to be movable on the ramp surface. The release handle is mounted on the transceiver module and is coupled to the actuator. Rotating the release handle in a first direction causes the actuator to move along the ramp surface toward the cage latch thereby moving the cage latch away from the interface surface. Rotating the release handle in a second direction causes the actuator to move along the ramp surface toward the interface surface and away from the cage latch.

Description:
BACKGROUND 
     This invention relates to a pluggable transceiver module for use in a connector system. The transceiver module has an actuator that releases the module from a cage. 
     Fiber optic systems are increasingly used for transmitting data signals. Typically, when data is transmitted by an optical network, it must be converted from an electrical signal to a light signal, and visa versa. In order to effectuate the conversion between electrical and optical signals, a transceiver module is often used at both ends of a fiber optic cable. Each transceiver module typically contains a laser transmitter circuit capable of converting electrical signals to optical signals, and an optical receiver capable of converting received optical signals back into electrical signals. 
     Typically, a transceiver module is electrically interfaced with a host device, such as a host computer, switching hub, network router, switch box, computer I/O or the like. Often, the transceiver module is the weakest link in a system, that is, it is most subject to failure and will need to be replaced. Consequently, in many applications it is desirable for the transceiver modules to be “hot-pluggable,” that is, the transceiver module may be inserted into, and removed from, the host system without removing electrical power. In this way, if a signal transceiver module fails, it can more readily be removed from the host device and replaced with a new module without having to perform a soldering or similar operation. 
     Consequently, several pluggable transceiver module designs and standards have been introduced in which a pluggable transceiver module plugs into a receptacle which is electronically connected to a host circuit board. For example, such as standard is delineated in the Small Form-Factor Pluggable (SFP) Transceiver Multi-Source Agreement (MSA), dated Sep. 14, 2000. Such standards define a receptacle or cage that receives a transceiver module. The cage includes a cage tongue or latch. The cage latch also includes a slot. The transceiver module includes a latch boss that projects from the module and fits into the slot of the cage latch. In this way, the cage latch holds the transceiver module in the cage when the module in inserted in the cage. The transceiver module also includes an actuator configured to adjustably engage the cage latch deflecting it away from the latch boss thereby releasing the latch boss, and thus the transceiver module, from the cage. 
     Although various standards have been given for the configuration of the transceiver module and the cage, variations between manufacturers exist as to some of the specific dimensions and configurations. Consequently, even for a SFP transceiver module and cage that comports with the MSA standard, it is not always known how far the actuator must be moved in order to deflect the cage latch sufficiently to release the transceiver module. A configuration for releasing the transceiver module that is more consistent from manufacturer to manufacturer, regardless of the specific configurations, would be an improvement to the art. 
     SUMMARY 
     The present invention is a transceiver module for use in a data transmission system. The transceiver module has an interface surface and is received within a cage. The cage has a cage latch that retains the transceiver module. The transceiver module has a ramp, an actuator and a release handle. The ramp is located on the interface surface of the transceiver module and has a ramp surface that slopes away from the interface surface of the transceiver module and toward the cage latch. The actuator is adjacent the interface surface of the transceiver module and is configured to be movable on the ramp surface. The release handle is mounted on the transceiver module and is coupled to the actuator. Rotating the release handle in a first direction causes the actuator to move along the ramp surface toward the cage latch thereby moving the cage latch away from the interface surface. Rotating the release handle in a second direction causes the actuator to move along the ramp surface toward the interface surface and away from the cage latch. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings are included to provide a further understanding of the present invention and are incorporated in and constitute a part of this specification. The drawings illustrate the embodiments of the present invention and together with the description serve to explain the principles of the invention. Other embodiments of the present invention and many of the intended advantages of the present invention will be readily appreciated as they become better understood by reference to the following detailed description. The elements of the drawings are not necessarily to scale relative to each other. Like reference numerals designate corresponding similar parts. 
         FIG. 1  illustrates a printed circuit board having a cage mounted thereon and a transceiver module plugged into the cage in accordance with the present invention. 
         FIG. 2  illustrates the transceiver module slightly removed from the cage in the cage in accordance with the present invention. 
         FIG. 3  illustrates the transceiver module removed from the cage. 
         FIG. 4  illustrates an actuator from the transceiver module. 
         FIG. 5  illustrates the transceiver module partially disassembled. 
         FIGS. 6A–6C  illustrate various positions of a release handle of the transceiver module. 
     
    
    
     DETAILED DESCRIPTION 
     In the following Detailed Description, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. In this regard, directional terminology, such as “top,” “bottom,” “front,” “back,” “leading,” “trailing,” etc., is used with reference to the orientation of the Figure(s) being described. Because components of embodiments of the present invention can be positioned in a number of different orientations, the directional terminology is used for purposes of illustration and is in no way limiting. It is to be understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the present invention. The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims. 
       FIG. 1  illustrates transceiver module  10 , face plate  11 , cage  12 , and printed circuit board (PCB)  14  in accordance with the present invention. Cage  12  is shown mounted to PCB  14 . Cage  12  can be secured to PCB  14  in various ways consistent with present invention. Face plate  11  is fixed the PCB  14  and typically includes a plurality of openings. Cage  12  is illustrated extending through one of the openings in face plate  11 . Cage  12  may be further secured to faceplate  11  with outwardly-extending prongs or springs or the like. Only a single cage  12  is illustrated extending through faceplate  11  for ease of illustration, but one skilled in the art will recognize that a multiplicity of cages can be mounted to PCB  14  and extend through faceplate  11  to receive a multiplicity of transceivers in accordance with the present invention. 
     Cage  12  also includes cage latch  16 . Transceiver module  10  is shown inserted into cage  12  and secured by cage latch  16 . Cage latch  16  is biased so that it tends to move toward transceiver module  10  thereby securing transceiver module  10  within cage  12 . Cage latch  16  is also flexible such that it can be moved away from transceiver module  10  so that transceiver module  10  can be extracted from cage  12 , as will be described in more detail below. 
     Transceiver module  10  includes release handle  18 . In order to extract transceiver module  10  from cage  12  release handle may be rotated in order to release transceiver module  10  from cage latch  16  such that transceiver module  10  may be slid out of cage  12 . Transceiver module  10  includes input/output terminal  20  in its front face  21 . Input/output terminal  20  may function as an optical input or optical output. In other embodiments, multiple input/output terminals  20  may be used to provide both input and output for optical and electrical signals to and from transceiver module. A single input/output terminal  20  is illustrated for ease of explanation. Front face  21  is referred to as being at the front of transceiver module  10 . However, in this regard, such directional terminology is used with reference to the orientation of the figures being described and is in no way meant to be limiting. One skilled in the art will recognize that components of embodiments of the present invention can be positioned in a number of different orientations. 
     In operation, optical and electrical signals can be transmitted to and from a destination or source that is plugged into input/output terminal  20  to transceiver module  10 . When transceiver module  10  is plugged into cage  12 , it is in electrical communication with PCB  14  via the connections therebetween. Thus, signals can be sent to and from the PCB via transceiver module  10 . Transceiver module  10  in hot pluggable and may be removed from cage  12  and replaced. 
       FIG. 2  illustrates transceiver module  10  extracted slightly from cage  12  in accordance with the present invention. Cage  12  is shown mounted to PCB  14 . Cage latch  16  is illustrated extending out from PCB  14 . The front edge  17  of latch  16 , that is, the edge closest to front face  21  of transceiver module  10 , is curved slightly in a direction away from transceiver module  10 , forming a sloped ramp. Cage latch  16  also includes latch slot  24 . Transceiver module  10  includes module cover  26  and latch boss  22 . Module cover  26  is configured to fit over transceiver module  10  and helps secure module  10  in cage  12  when it is inserted therein, and also helps secure release handle  18  to transceiver module  10 . 
     Latch boss  22  is configured to engage cage latch  16 . Specifically, when transceiver module  10  is inserted into cage  12 , latch boss  22  deflects latch  16  slightly away from transceiver module  10  such that latch boss  22  travels past the front edge  17  of latch  16  and toward latch slot  24 . Since front edge  17  of latch  16  is sloped away from latch boss  22 , latch boss  22  more easily slides past latch  16  as module  10  slides into cage  12 . When transceiver module  10  is fully inserted into cage  12 , latch boss  22  is aligned with latch slot  24  such that latch boss  22  extends through latch slot  24 . Latch  16  is configured with a bias such that when latch boss  22  is fully aligned with latch slot  24 , latch  16  transitions back toward transceiver module  10  and rests against cage latch stop  23 . In this way, transceiver module  10  will be locked into cage  12 . In one embodiment of the present invention, latch boss  22  and latch slot  22  are configured to be triangular shaped and complement each other such that latch boss  22  fits through latch slot  24 . 
     In order to remove transceiver module  10  from cage  12 , latch  16  must be moved away from transceiver module  10  and off cage latch stop  23  a sufficient distance so that that latch boss  22  is removed from latch slot  24  and clears the front edge of latch slot  24 , as will be described more fully below. 
       FIG. 3  illustrates transceiver module  10  in accordance with the present invention, with module cover  26  removed to show additional detail. Transceiver module  10  has module interface surface  28 . Latch boss  22  extends away from module interface surface  28  such that the top of latch boss  22  is raised relative to module interface surface  28 . In one embodiment, latch boss  22  extends away from module interface surface  28  to form a triangular-shaped raised portion. Cage latch stop  23  may also be provide to help guide actuator  30  as will be described more fully below. 
     Also included on transceiver module  10  is actuator  30 , which is situated in a slot (shown as actuator slot  40  in  FIG. 5  discussed below) that is provided in module interface surface  28 . Actuator  30  includes actuator arm  38 . Release handle  18  is mounted in grooves or similar openings on transceiver module  10  and includes cam portion  32 . Handle  18  is mounted on transceiver module  10  such that it can be rotated relative to transceiver module  10 . 
     In  FIG. 3 , release handle  18  is shown in a closed or 0° position, such that it is generally parallel with the front face  21  of transceiver module  10 . Cam portion  32  of release handle  18  engages actuator  30 . In one embodiment, actuator arm  38  encloses cam portion  32  of release handle  18 . As release handle  18  is rotated from the closed position, cam portion  32  moves away from the front of transceiver module  10  with the rotation. Since actuator arm  38  encloses cam portion  32  and actuator arm  38  is fixed to actuator  30 , actuator  30  moves in an approximately linear direction away from the front face  21  of transceiver module  10  with this rotation of release handle  18 . 
     When transceiver module  10  is plugged into cage  12 , release handle  18  can be used to release transceiver module  10  from cage  12  so that it can be extracted therefrom. As release handle  18  is rotated from the closed position, actuator  30  moves approximately linearly along module surface  28  of transceiver module  10  until it engages latch  16 . Latch  16  is then deflected away from module surface  28  of transceiver module  10  and away from latch boss  22 . In this way, a movement of actuator  30  against latch  16  provides clearance for latch boss  22  to pass out of latch slot  24 . Once adequate clearance is provided, transceiver module  10  can be removed from cage  12 . 
       FIG. 4  illustrates actuator  30  removed from transceiver module  10  and  FIG. 5  illustrates transceiver module  10  with actuator  30  removed therefrom. In  FIG. 5 , module cover  26  has also been removed. Actuator  30  includes actuator arm  38  and first and second actuator tines  34  and  36 . Module interface surface  28  includes actuator slot  40 . Actuator slot  40  is a recessed area into which actuator  30  fits. Actuator slot  40  has a surface that is recessed relative to module interface surface  28 . In one embodiment, actuator slot  40  is configured with sides to retain actuator  30  such that actuator  30  can move toward and away from the front of transceiver module  10 , but so that it cannot move laterally. In addition, actuator slot may include cage latch stop  23 . Cage latch stop  23  may be configured to compliment a slotted portion of actuator  30 , between tines  34  and  36 , thereby proving guiding to actuator  30  as it moves toward and away from front face  21  of transceiver module  10 . 
     One end of actuator slot  40  is configured with first and second actuation ramps  42  and  44 . First and second actuation ramps  42  and  44  are sloped from actuator slot  40  up to module interface surface  28 . When actuator  30  is placed in actuator slot  40 , first and second actuator tines  34  and  36  are configured to engage first and second actuation ramps  42  and  44 . In this way, as actuator  30  moves away from the front face  21  of transceiver module  10 , first and second actuator tines  34  and  36  move up first and second actuation ramps  42  and  44 . Consequently, as first and second actuator tines  34  and  36  move up first and second actuation ramps  42  and  44 , they move in a direction away from module surface  28 . When transceiver module  10  is fully inserted in cage  12 , such motion of first and second actuator tines  34  and  36  will cause them to engage latch  16  and deflect it away from module  10 . Consequently, as actuator  30  moves away from the front face  21  of transceiver module  10 , latch  16  will be forced in a direction away from transceiver module  10  by first and second actuator tines  34  and  36 . 
     In order to remove transceiver module  10  from full engagement in cage  12 , release handle  18  is rotated from its closed position. Such rotation will slide actuator  30  within actuator slot  40  in a direction away from the front of transceiver module  10 . This will cause first and second actuator tines  34  and  36  to move up first and second actuation ramps  42  and  44  in a direction away from module surface  28  thereby engaging cage latch  16 . This will cause cage latch  16  to also move in the direction away from module surface  28 . This will push cage latch  16  off latch boss  22  thereby providing sufficient clearance between latch boss  22  and latch slot  24  such that transceiver module  10  can be removed from cage  12 . 
     Actuator  30  is relatively flat and first and second actuator tines  34  and  36  are configured to extend upward from actuator  30 . In one embodiment, first and second actuator tines  34  and  36  are sloped upward much like the tips of snow skis. This can help facilitate first and second actuator tines  34  and  36  moving up first and second actuation ramps  42  and  44 . 
     Actuator  30  may also have a groove between first and second tines  34  and  36  such that when latch boss  22  is placed between first and second actuation ramps  42  and  44 , as illustrated in the Figures, actuator  30  will not impeded by cage latch stop  23  or by latch boss  22  as it moves away from the front face  21  of transceiver module  10  and travels up first and second actuation ramps  42  and  44 . Placing latch boss  22  immediately adjacent or between first and second actuation ramps  42  and  44  ensures that when first and second tines  34  and  36  move up first and second actuation ramps  42  and  44  they will engage release latch  16  immediately adjacent slot  24 . This will provide deflection of latch  16  at the point where latch boss  22  engages slot  24  thereby providing the release of boss  22  from slot  24 . 
     Unlike prior systems, transceiver module  10  in accordance with the present invention does not rely on a wedge-shaped actuator to deflect the cage latch. With prior wedge-shaped actuators, the shape of both the actuator and of the cage latch, of even the specific slope of its front edge, were all critical to defining how much the wedge must slide in order to deflect the latch sufficiently to release the transceiver module. Consequently, with prior systems, the amount that the wedge must slide in order to deflect the latch sufficiently to release the transceiver module varies from manufacturer to manufacturer, since manufacturers often have slightly different dimensions and shapes for their actuators and cage latches. For example, even when a cage is designed according to the MSA standards, the curvature or radius of the cage latch will vary by manufacturer. In this way, the amount of rotation of a release handle required to release the module is not readily known, and will vary for each manufacturer. 
     With the present invention, transceiver module  10  can be configured to precisely determine the amount that release handle  18  must be rotated in order to release transceiver module  10  from cage  12 , regardless of the manufacturer that made cage  12 . First and second actuator tines  34  and  36  are configured so that when release handle  18  is in the closed position tines  34  and  36  just engage first and second actuation ramps  42  and  44 , but are not moving up the ramps. In this way, first and second actuator tines  34  and  36  do not extend beyond module interface surface  28 . Thus, they do not engage and move cage latch  16  away from module interface surface  28  in this state. First and second actuator tines  34  and  36  are also configured, however, that when release handle  18  is rotated to a position past the closed position, tines  34  and  36  will have moved up first and second actuation ramps  42  and  44 . In this way, first and second actuator tines  34  and  36  do extend beyond module interface surface  28  a sufficient amount to engage and move cage latch  16  away from module interface surface  28  and release transceiver module  10  from cage  12 . Tines  34  and  36  may be specifically configured to predictably design the amount of rotation of handle  18  required to release transceiver module  10  from cage  12 . 
       FIGS. 6A–6C  illustrate various positions of release handle  18  for transceiver module  10 . In  FIG. 6A , release handle  18  is illustrated in the closed position. As indicated previously, in this position release handle  18  is said to be at 0°. In this position, actuator  30  is in a location toward the front face  21  of transceiver module  10 . In this position, first and second actuator tines  34  and  36  have not moved up first and second actuator ramps  42  and  44 . Consequently, first and second actuator tines  34  and  36  are not significantly above module surface  28 . Thus, first and second actuator tines  34  and  36  do not engage latch  16  sufficiently to move it away from module surface  28 . In this position, latch boss  22  is fully engaged with latch slot  24  so that transceiver module  10  cannot be removed from cage  12 . 
       FIG. 6B  illustrates release handle  18  rotated slightly from the closed position. This position is referred to as the 50° position, as release handle  18  has been rotated approximately 50° relative to its initial closed position or relative to front face  21  of transceiver module  10 . In this position, cam portion  32  of release handle  18  has engaged actuator  30 , by actuator arm  38  enclosure of cam portion  32 , and moved actuator  30  away from the front face  21  of transceiver module  10 . Thus, first and second actuator tines  34  and  36  have moved up first and second actuation ramps  42  and  44  such that they engage latch  16 . In one embodiment of the present invention, when release handle  18  reaches the 50° position, first and second actuator tines  34  and  36  engage and move latch  16  sufficiently far away from module surface  28  so as to release latch boss  22  from latch slot  24 . In this way, transceiver module  10  can be removed from cage  12  when release handle  18  is rotated to the 50° position. Advantageously, the release of transceiver module  10  at the 50° position can be achieved regardless of the specific shape and dimensions of cage latch  16  or of front edge  17 . 
       FIG. 6C  illustrates release handle  18  rotated 90° relative to it initial position on transceiver module  10 . In one embodiment of the present invention, when release handle  18  has rotated to this 90°, first and second actuator tines  34  and  36  transition fully up first and second actuation ramps  42  and  44  such that latch  16  is deflected a maximum distance away from module surface  28 . When release handle  18  reaches the 90° position, first and second actuator tines  34  and  36  move latch  16  sufficiently far away from module surface  28  so as to release latch boss  22  from latch slot  24 . In this way, transceiver module  10  can be removed from cage  12  when release handle  18  is rotated to the 90° position. In one embodiment of the present invention, the release of transceiver module  10  at the 90° position can be achieved regardless of the specific shape and dimensions of cage latch  16  or front edge  17 . 
     In each embodiment, first and second actuation ramps  42  and  44  are illustrated as having a generally linear slope, but ramps  42  and  44  can also be designed with non-linear slopes. For example, they could be designed with a curved slope such that the actuator would need travel only a short distance from the front face  21  of transceiver module to move a sufficient distance away from the module surface  28  to deflect the cage latch  16 . 
     Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and/or equivalent implementations may be substituted for the specific embodiments shown and described without departing from the scope of the present invention. For example, a release handle has been illustrated as causing the actuator to slide up the ramp of the transceiver module, but one skilled in the art will recognize that other mechanisms can be used to slide the actuator up the ramp in order to release the transceiver module from the case. This application is intended to cover any adaptations or variations of the specific embodiments discussed herein. Therefore, it is intended that this invention be limited only by the claims and the equivalents thereof.