An apparatus, main heat sink and secondary heat sink assembly

Abstract

An apparatus for telecommunications equipment is provided. The apparatus comprises: a main heat sink, wherein the main heat sink is configured to be in thermal contact with processing circuitry; and one or more secondary heat sinks, wherein the one or more secondary heat sinks are thermally coupled to a cage configured to receive a signal connector; wherein the main heat sink and the one or more secondary heat sink are connected. A main heat sink and a secondary heat sink, and a secondary heat sink assembly for the apparatus are also provided.

Description

[0001] An Apparatus, Main Heat Sink and Secondary Heat Sink Assembly

[0002] TECHNICAL FIELD

[0003] The present disclosure relates to an apparatus for telecommunications equipment. In some aspects, the present disclosure relates to main and secondary heat sinks for the apparatus.

[0004] BACKGROUND

[0005] Standard Quad Small Form factor Pluggable (QSFP) interface modules, such as QSFP28 modules, are high speed optical modules with rates of up to 100Gb / s with 4 lanes at 25Gb / s, and are designed for a maximum power consumption of 5 Watts.

[0006] Increases in capacity demands, especially in data centres, combined with the desire to decrease the equipment real estate occupation has led to the creation of Quad Small Form factor Pluggable Double Density (QSFP-DD) modules, as the smallest form factor for 400G transceivers.

[0007] QSFP-DD is fully compliant with IEEE802.3bs and QSFP-DD MSA standards. The “double density” term refers to the doubling of the number of high-speed electrical interfaces that the module supports compared with a standard QSFP28 module. The data rate of each channel can reach 25Gb / s through NRZ modulation technology, realizing 200Gb / s network transmission. Also, the data rate of each channel can reach 50Gb / s using PAM4 modulation technology to achieve 400G network transmission, which is suitable for high-performance Data Center and cloud network. QSFP-DD modules thereby offer increased bandwidth density whilst retaining backward compatibility to lower-speed QSFP pluggable modules and cables. This has made QSFP-DD modules popular among the fibre optic manufacturers. Due to the backward compatibility with QSFP28 module, the mechanics of the QSFP-DD module is similar to other QSFP modules. However, QSFP-DD modules have increased length.

[0008] In addition, to the increased bandwidth capacity provided by the QSFP-DD module, power consumption is also increased to values of 16-23 W. This greatly increases the power density of heat to be dissipated in small space like the module cage which houses the pluggable module. This may set an unacceptable limit for the operating environment temperature for host equipment, such as interface module assemblies, e.g. in telecoms applications. For example, ETSI / Ansi Standards set a maximum environment temperature of 55°C for the host equipment. When QSFP-DD modules are included, it can be challenging to meet operating temperature requirements for the equipment (e.g. in which the QSFP-DD modules are provided) in such environments.

[0009] The issue of thermal management of high power component becomes more challenging in case of sealed mechanics. Figures 1a and 1 b, illustrate a previously proposed apparatus 100 applying seal mechanics principles. Sealed mechanics Telecommunications equipment is a building practice in which airflow is not allowed inside a space 102 formed between main heat sinks 104, 106, such as top and bottom heat sinks, of the equipment. The interface modules, e.g. the QSFP-DD modules 110,112 and a main PCB 108 are provided inside the space 102. Accordingly, cooling airflow does not directly contact the electrical components, e.g. the interface modules 110, 112, main PCB 108 and any electrical components 114 mounted on the PCB. In some arrangements, a dust filter (not shown) may be provided to remove dust and this may force the equipment operator to perform further maintenance operations to periodically the cleaning of such dust filter. In the case of sealed mechanics, the airflow is allowed only to the main heat sinks 104, 106. Accordingly, a dust filter may not be provided. The main heat sinks 104, 106 are thermally connected with the interface modules 110, 112 and other electrical components 114 through thermal pads 116, 118.

[0010] QSFP-DD optical modules are more difficult to thermally manage than previous QSFP modules, since their relatively high thermal power output is concentrated in a similarly sized space within the assembly, creating a hot point in the assembly. In equipment operating with sealed mechanics, thermal management becomes more challenging since, as depicted in Figure 2, even with a low profile heat sink 120 there is a thermal pad 116 between the QSFP-DD module, e.g. the heat sink 120 of the QSFP-DD module, and the main heat sink 104, 106 of the assembly. The thermal pad provides some thermal resistance to heat transmission between the QSFP-DD module and the main heat sink. Due to the high power consumption of the QSFP-DD, the thermal pad 116 may not allow sufficient heat transfer to maintain a desirable temperature of the QSFP-DD module. As a result, the case temperature of the QSFP-DD module can rise above a desired limit, which may make it difficult to achieve a desired equipment environment specification, e.g. of the apparatus 100, in ambient temperatures of 55°C or 65°C.

[0011] SUMMARY

[0012] According to an aspect of the present disclosure, there is provided an apparatus for telecommunications equipment. The apparatus comprises a main heat sink, wherein the main heat sink is configured to be in thermal contact with processing circuitry. The apparatus further comprises one or more secondary heat sinks, wherein the one or more secondary heat sinks are thermally coupled to a cage configured to receive a signal connector. The main heat sink is separate to the one or more secondary heat sink.

[0013] In some aspects, the main heat sink and the one or more secondary heat sinks have different thermal characteristics.

[0014] In some aspects, the main heat sink and the one or more secondary heat sinks comprise heat dissipation fins, wherein a pitch of the heat dissipation fins of the secondary heat sink is smaller than a pitch of the heat dissipation fins of the main heat sink.

[0015] In some aspects, the main heat sink and the one or more secondary heat sink are connected.

[0016] In some aspects, the main heat sink and the one or more secondary heat sink are connected to provide for an electrical connection.

[0017] In some aspects, the apparatus further comprises a seal provided between the main heat sink and the secondary heat sink.

[0018] According to an aspect of the present disclosure, there is provided an apparatus for telecommunications equipment, wherein the main heat sink comprises a heat sink body, arranged to be in thermal contact with processing circuitry and further comprises an opening through the heat sink body, the opening configured to receive a separate secondary heat sink such that the secondary heat sink is thermally coupled to a cage configured to receive a signal connector.

[0019] According to an aspect of the present disclosure, there is provided a secondary heat sink for an apparatus for telecommunications equipment, wherein the apparatus comprises a main heat sink comprising an opening through the main heat sink, wherein the secondary heat sink comprises a heat sink body and is receivable within the opening in the separate main seat sink, such that the heat sink body is in thermal contact with a cage configured to receive a signal connector.

[0020] According to an aspect of the present disclosure, there is provided a secondary heat sink assembly for an apparatus for telecommunications equipment, the secondary heat sink assembly comprising: a cage for receiving a signal connector, wherein the cage comprises an interface surface and an opening formed in the interface surface; and the secondary heat sink of claim 15, wherein the heat sink body of the secondary heat sink comprises a thermal contact portion configured to be in thermal contact with the signal connector inside the cage.

[0021] To avoid unnecessary duplication of effort and repetition of text in the specification, certain features are described in relation to only one or several aspects or embodiments of the invention. However, it is to be understood that, where it is technically possible, features described in relation to any aspect or embodiment of the invention may also be used with any other aspect or embodiment of the invention. For example, features described in relation to the first, second, third and fourth mentioned aspect may be combined with the features of the other mentioned aspects and vice versa.

[0022] BRIEF DESCRIPTION OF THE DRAWINGS

[0023] For a better understanding of the present invention, and to show more clearly how it may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which:

[0024] Figure 1a is a schematic cross-sectional view of a previously proposed apparatus; Figure 1 b is a front perspective view of the previously proposed apparatus;

[0025] Figure 2 is a front perspective view of a cage, cage heat sink and thermal pad of a previously proposed apparatus;

[0026] Figure 3 is a schematic cross-sectional view of an apparatus according to arrangements of the present disclosure;

[0027] Figure 4 is a top perspective view of a secondary heat sink, according to the present disclosure, for the apparatus shown in Figure 3;

[0028] Figure 5a is a partially exploded perspective view of a second heat sink assembly, according to the present disclosure, for the apparatus according to arrangements of the present disclosure;

[0029] Figure 5b is a cross-sectional view of a cage and secondary heat sink of the secondary heat sink assembly;

[0030] Figure 6 is a top perspective view of an electrically conductive element for the secondary heat sink assembly;

[0031] Figure 7 is a partially exploded perspective view of the second heat sink assembly, comprising the electrically conductive element;

[0032] Figure 8 is a cross sectional view showing the detail of an interference connection between the electrically conductive element and the secondary heat sink of the secondary heat sink assembly;

[0033] Figure 9 is a top perspective view of the secondary heat sink assembly;

[0034] Figures 10a and 10b are top and bottom perspective views of the main heat sink for the apparatus sown in Figure 3; Figures 11a and 11 b are top perspective views of the apparatus with the main heat sink being omitted in Figure 11a; and

[0035] Figures 12a, 12b and 12c are perspective, front and perspective views respectively of an apparatus according to another arrangement of the present disclosure, with the main heat sink being omitted in Figure 12a.

[0036] DETAILED DESCRIPTION

[0037] With reference to Figure 3, an apparatus 300, such as an interface module assembly, e.g. for telecommunications equipment, according to arrangements of the present disclosure will now be described.

[0038] The apparatus 300 comprises a main heat sink 302. The main heat sink 302 may be a top heat sink provided at a top of the apparatus. Alternatively, the main heat sink may be a bottom heat sink provided at a bottom of the apparatus 300. The apparatus may comprise both a top heat sink and a bottom heat sink which may be similar to one another although provided at the top and bottom of the apparatus respectively. Features described in relation to the main heat sink may therefore refer to either or both of the top and bottom heat sinks of the apparatus. Similarly, features described in relation to either or both of the top and bottom heat sinks may be features of the main heat sink.

[0039] The main heat sink 302 may at least partially form an internal space 306 inside the apparatus for receiving one or more signal connectors 310, 312. The top heat sink may form a top wall of the internal space. The bottom heat sink may similarly at least partially form the internal space of the interface space assembly. For example, the bottom heat sink may form a bottom wall of the internal space. Accordingly, the internal space 306 may be formed between the top and bottom heat sinks 302, 304.

[0040] The apparatus 300 may be configured to operate according to sealed mechanics principles. The internal space 306 may be sealed to prevent or restrict a flow or air and / or dust into and / or out of the internal space. For example, the internal space may be sealed, at least partially, by the top heat sink 302 and bottom heat sink 304 (when provided). In some arrangements, the top and bottom heat sinks 302, 304 may be configured to form the sealed internal space of the apparatus between them.

[0041] The main heat sink 302 may comprise a heat sink body 302a and a plurality of heat dissipation fins 302b. At least part of the heat sink body 302a may be substantially planar, e.g. in the form of a plate, and may form a wall of the internal space 306, such as the top wall. Additionally or alternatively, the heat sink body 302a may be arranged at least partially inside the internal space 306 so that the heat sink body is arranged to be in thermal contact with processing circuitry, such as the electrical components 114 and / or one or more signal connectors 310, e.g. within the internal space 306. The heat dissipation fins 302b may be thermally connected to the heat sink body 302a. For example, the heat dissipation fins 302b may be integrally formed with the heat sink body 302a. The heat dissipation fins 302b may project from the heat sink body 302a in a direction away from the internal space 306.

[0042] The apparatus 300 may comprise a housing 350 configured to define an air flow channel 352 outside the internal space for cooling air to flow through over the main heat sink 302. The heat dissipation fins 302b may be arranged at least partially within the air flow within the air flow channel 352. When the apparatus comprises the top and bottom heat sinks 302, 304, the housing 350 may be configured to define air flow channels over both the top and bottom heat sinks and the heat dissipation fins of the top and bottom heat sinks may be arranged in the respective air flow channels defined by the housing 350. The apparatus 300 may further comprise a fluid moving device, such as a fan 360, configured to drive a flow or air, or other cooling fluid through the air flow cannels 352.

[0043] Although in the arrangement shown in the Figures, the main heat sink 302 and bottom heat sink 304 are provided at the top and bottom of the apparatus 300 respectively, in other arrangements, the main and bottom heat sinks may instead be provided on any other opposite sides of the apparatus, such as on opposing lateral side. In such arrangements, the heat dissipation fins of the main and bottom heat sinks may extend laterally from the heat sink bodies into air flow channels formed on either lateral side of the internal space and heat sinks. The apparatus 300 may comprise one or more cages, not depicted in Figure 3, inside the internal space 306 for receiving the signal connectors 310, 312, e.g. respective ones of the signal connectors. The apparatus 300 may comprise a PCB 301 , and a plurality of signal connector interfaces, not shown, coupled to the PCB 301. The combination of the cages and associated signal connector interface may be referred to as an interface module. Accordingly, the apparatus 300 may be referred to as an interface module assembly. The apparatus may further comprise other processing circuitry, such as the electrical components 114, which may be mounted on the PCB. In the arrangement shown, the PCB 301 is mounted substantially horizontally in the internal space. However, in other arrangements, the PCB may be mounted vertically or in any other orientation. The PCB 301 may be mounted such that the sides of the PCB face the main heat sink 302 and bottom heat sink 304 respectively.

[0044] The signal connectors 310, 312, e.g. provided within the internal space 306, may be pluggable signal connector modules, e.g. pluggable optical modules, such as Small Formfactor Plugable (SFP) Optical modules, e.g. QSFP28 or QSFP-DD modules.

[0045] The cages may be mounted on the PCB 301 and configured to guide the signal connectors 310, 312 towards the signal connector interfaces, so that the signal connectors are connected to the signal connector interfaces when the signal connectors are received within the cages. As depicted, the signal connectors may be arranged on either side of the PCB 301. Accordingly, the cages may similarly be provided on either side of the PCB for receiving the signal connectors. For example, the cages may be mounted on either side of the PCB.

[0046] Although only a single signal connector 310 is depicted on the top side of the PCB 301 and a single signal connector 312 is depicted on the bottom side of the PCB in the vertical section of the apparatus 300 depicted in Figure 3, it will be appreciated that a plurality of the signal connectors 310, 312 may be provided on either or both sides of the PCB. For example, a plurality of the signal connector interfaces and cages for receiving signal connectors may be spaced across the top and bottom of the PCB in a lateral direction of the apparatus 300.

[0047] The amount of heat generated by signal connectors may vary depending on the type of signal connector. For example, QSFP-DD optical modules may have a greater heat output than QSFP23 modules. It may be desirable for signal connectors having both higher and lower heat output to be provided within the apparatus. For example, it may be desirable for both QSFP28 optical modules and QSFP-DD optical modules to be provided.

[0048] The heat sink body 302a of the main heat sink may be thermally connected to the processing circuitry, e.g. one or more of the signal connectors, and / or cages in which the signal connectors are received via thermal pads 116, e.g. respective thermal pads. In some arrangements, the apparatus 308 may comprise one or more signal connector heat sinks 120, which may be arranged between the thermal pads 116 and the signal connectors and / or cages in which the signal connectors are received, e.g. between respective pairs of thermal pads and signal connectors / cages. In other words, one or more of the signal connectors and / or cages may be thermally connectors to the main heat sink in the same way as in the arrangements illustrated in Figures 1a, 1 b and 2.

[0049] In order to provide improved heat dissipation from one or more others of the signal connectors 310, 312 provided within the apparatus 300, the main heat sink 302 may comprise an opening 302c through the heat sink body 302a into the internal space of the apparatus. The opening 302c may be at least partially aligned with a cage for receiving one of the others of the signal connectors 310. The apparatus further comprises a secondary heat sink 400 connected to the main heat sink. For example, the secondary heat sink 400 may be received within the opening 302c. The secondary heat sink is arranged in thermal contact with one of the others of the signal connectors, e.g. provided within the internal space, and / or a cage in which one of the others of the signal connectors is received. For example, the secondary heat sink 400 may be arranged in thermal contact with the cage that the opening 302c is at least partially aligned with and / or the signal connector received therein. As described in greater detail below, the secondary heat sink 400 may be arrangeable in direct thermal contact with the one of the others of the signal connectors 310, 312.

[0050] The secondary heat sink 400 may comprise a heat sink body 402 configured to be arranged in thermal contact, e.g. direct thermal contact, with one of the others of the signal connectors, e.g. within the internal space, and / or a cage in which the signal connector is provided. For example, the heat sink body 402 may be at least partially or substantially completely disposed within the internal space 306. The secondary heat sink 400 may further comprise a plurality of heat dissipation fins 404 thermally coupled to the heat sink body. For example, the plurality of heat dissipation fins 404 may be integrally formed with the heat sink body 401 . The heat dissipation fins 404 may project from the heat sink body 402. The heat dissipation fins 404 may extend principally in a first direction Di of the secondary heat sink.

[0051] When the secondary heat sink 400 is received within the opening 302c in the heat sink body of the main heat sink, such that heat sink body of the secondary heat sink is in thermally contact with one of the others of the signal connectors within the internal space, the heat dissipation fins 404 may project through the opening 302c in the main heat sink so as to be at least partially outside the internal space 306. For example, the heat dissipation fins 404 of the secondary heat sink may be at least partially aligned with the heat dissipation fins 302b of the main heat sink in a direction into and out of the opening 302c. The heat dissipation fins 404 of the secondary heat sink may be arranged within the flow of air through the air channel 352 defined by the housing 350.

[0052] As described below, the heat sink body 402 may be arranged in direct contact with one of the others of the signal connectors without an interposed thermal pad being provided between the secondary heat sink 400 and the other of the signal connectors. Hence, a rate of heat dissipation, to the external environment of the apparatus, from the other of the signal connectors 310, 312 via the secondary heat sink 400 may be greater than a rate of heat dissipation from the signal connectors via the main heat sink. Accordingly, when a signal connector having a higher heat output, such as a QSFP-DD optical module, is installed within the apparatus 300 so as to be in thermal contact with the secondary heat sink 400 rather than the main heat sink, a temperature of the apparatus 300 may be reduced.

[0053] With reference to Figures 4, 5a and 5b, the heat sink body 402 may comprise a substantially planar portion 402a, e.g. in the shape of a plate. A shape of the substantially planar portion 402a, may be configured to correspond to a shape of the opening 302c in the primary heat sink. Close correspondence between the shape of the substantially planar portion 402a and the opening 302c may improve sealing between the main heat sink and the secondary heat sink, as described below. As depicted, the heat dissipation fins 404 project from the heat sink body on one side of the substantially planar portion 402a. The heat sink body 402 further comprises a thermal contacting portion 402b on an opposite side of the substantially planar portion from the heat dissipation fins. The thermal contacting portion 402b is configured to thermally contact, e.g. directly contact the other of the signal connectors. As shown in Figure 5b, the thermal contacting portion 402b may comprise a pad or boss projecting outwardly from the substantially planar portion 402.

[0054] Referring now to Figures 5a and 5b, a secondary heat sink assembly 500 according to arrangements of the present disclosure will now be described. The secondary heat sink assembly 500 comprises components described as part of the apparatus 300 above. In other words, the secondary heat sink assembly may be a sub-assembly of the apparatus 300 and may be provided as part of the apparatus 300, for example, in place of the cage and secondary heat sink described above with reference to Figure 3. The features described in relation to the secondary heat sink assembly 500 may therefore equally apply to the apparatus 300.

[0055] The secondary heat sink assembly 500 comprises a cage 510 for receiving a signal connector, such as pluggable module, e.g. a SFP module, such as a QSFP28 or QSFP-DD module. For the reasons described herein, the cage 510 of the secondary heat sink assembly 500 may be particularly suitable for receiving a QSFP-DD module due to the improved heat dissipation properties provided by the secondary heat sink assembly 500 as part of the apparatus 300.

[0056] The cage 510 comprises a number of walls 512, such as an upper wall 512 and two opposing side walls 514, 516. The side walls 514, 316 may be arranged at an angle, e.g. perpendicular, to the upper wall 512 and may depend from either lateral side of the upper wall 512. In this way, the walls 514 of the cage 510 may enclose an interior space 518 of the cage for receiving the signal connector. An opening 517 for the signal connector may be formed between the upper wall 512 and the two opposing side walls 514, 516.

[0057] The secondary heat sink assembly 500 further comprises the secondary heat sink 400. One of the walls of the cage, such as the upper wall 512 defines an interface surface configured to interface with the heat sink body 402 of the secondary heat sink. In particular, the planar portion 402a of the heat sink body may be arranged in contact with the interface surface of the cage within the secondary heat sink assembly 500. An opening 519 may be formed in the interface surface, e.g. through the upper wall 512 of the cage, for the thermal contacting portion 402b of the secondary heat sink to project through the upper wall 512 into the interior space 518 inside the cage, as shown in Figure 5b, in order to contact the signal connector inside the cage 510.

[0058] As illustrated in Figures 5a and 5b, the secondary heat sink assembly 500 may further comprise a resiliently deformable clip 520. The resiliently deformable clip comprises a first clip 522 configured to couple to the cage 510, e.g. on one lateral side of the cage. For example, the first clip 522 may be configured to couple to a complementary clip 511 formed on one of the side walls 514, 516 of the cage. The resiliently deformable clip further comprises one or more second clips 524 configured to couple to the cage on an opposite side, e.g. opposite lateral side, of the cage 510 from the first clip 522. For example, the second clips 524 may be configured to couple to one or more, e.g. respective, complementary clips formed on the other of the side walls 514, 516 of the cage. As depicted, the heat sink body 402 may comprise gaps for the first clip 522 and or the second clips 524 to extend through to reach the complementary clips 511 formed on the cage 510.

[0059] The resiliently deformable clip 520 further comprises a resiliently deformable body part 526 configured to extend between the first and second clips on an opposite side of the second heat sink 400 from the cage 510. The resiliently deformable body may be resiliently deformable by virtue of a shape and / or material of the resiliently deformably body part. For example, resiliently deformably body part may be formed from a metal material and may comprise one or more bends over its length between the first and second clips 522, 524 configured such that deformation of the body part 526 causes the bends to be straightened or further bent, which deformation is resisted due to the material properties of the resiliently deformably body part 526.

[0060] The resiliently deformable body part 526 may be configured to engage the second heat sink 400 to retain the heat sink body 402 of the second heat sink in contact with the cage 510, e.g. with the interface surface, and / or the signal connector inside the cage. Additionally or alternatively, when the second heat sink 400 is urged to move away from the cage 510, e.g. during insertion of a signal connector into the interior space 518 of the cage as described below, the resilient resiliently deformable body part 526 may resiliently deform in order to bias the second heat sink 400 to return to the position in which the heat sink body 402 of the second heat sink in contact with the cage, e.g. the interface surface, and / or the signal connector inside the cage.

[0061] As illustrated in Figures 5a and 5b, the heat dissipation fins 404 of the secondary heat sink may comprise one or more areas, e.g. over the surface of the heat sink body 402, extending between the lateral sides of the secondary heat sink, in which a projection length of the heat dissipation fins, by which the heat dissipation fins project from the heat sink body is reduced. The resiliently deformable body part 526 may be aligned with the areas in which the projection length of the heat dissipation fins is reduced. In this way, the resiliently deformable body part 526 may be arranged closer to the heat sink body 402. Further, a height, e.g. maximum height, of the resiliently deformable body part 526 above the heat sink body 402 may be less than the projection length of the heat dissipation fins 404, e.g. a greatest projection length of the heat dissipation fins, from the heat sink body.

[0062] As shown in Figure 5b, the thermal contacting portion 402b may comprise a ramp surface 402c provided on a side of the thermal contacting portion facing the opening 517 into the interior space 518 of the cage. When the signal connector is installed through the opening 517 into the cage, the signal connector may engage the ramp surface 402c and urge the secondary heat sink, e.g. the thermal contacting portion 402b, out of the interior space, e.g. through the opening 519 in the interface surface.

[0063] As mentioned above, when the second heat sink 400 is urged to move away from the cage 510, the second heat sink may deform the resiliently deformable clip 520, which may urge the secondary heat sink 400 back against the cage 510 and / or signal connector by virtue of its resilience.

[0064] With reference to Figures 6 to 9, the secondary heat sink assembly 500 may further comprise an electrically conductive element 600. The electrically conductive element may be arranged in contact, e.g. electrical contact, with the secondary heat sink, e.g. the heat sink body 402. For example, the electrically conductive element 600 may be assembled against a surface of the substantially planar portion 402a of the heat sink body, e.g. on a side of the heat sink body from which the heat dissipation fins 404 project. As depicted, the electrically conductive element 600 may extend around, e.g. at least partially around, a perimeter of the heat sink body, e.g. around the heat dissipation fins 404. The electrically conductive element 600 may comprise a sheet metal component, e.g. a thin sheet metal component. The electrically conductive element 600 may comprise a substantially planar plate portion 602, which may be shaped to extend over at least a part of the surface of the planar portion 402a of the heat sink body around the heat dissipation fins 404.

[0065] The electrically conductive element 600 may be arranged within the secondary heat sink assembly 500 such that when the secondary heat sink assembly is installed into the apparatus 300, the electrically conductive element 600 is in contact, e.g. electrical contact, with the main heat sink 302 at one or more positions around the opening 302c in the main heat sink in which the secondary heat sink is received. The electrically conductive element 600 may be arranged between the main heat sink 302 and the secondary heat sink 400 around the opening.

[0066] As mentioned above, the electrically conductive element 600 may comprise a sheet metal component and may comprise a substantially planar plate portion 602. The electrically conductive element 600 may further comprise one or more contacting portions 604, which may comprise one or more portions of the electrically conductive element projecting out of the plane of the plate portion 602. The contacting portions 604 may be formed by bending a part of the electrically conductive element of out the plane of the plate portion 602. The contacting portions 604 may be resiliently deformable in a direction into and out of the plane of the plate portion 602. When the secondary heat sink assembly 500 comprising the electrically conductive element 600 is installed into the apparatus 300, and the electrically conductive element 600 is positioned between the main heat sink 302 and the secondary heat sink 400, the contacting portions 604 may be resiliently biased against the main heat sink in order to maintain the electrical connections between the secondary heat sink 400 and the main heat sink 302.

[0067] The electrically conductive element 600 may further comprise one or more interference connector portions 606 configured to be received within one or more, e.g. respective, interference fit bores 402d formed in the secondary heat sink, e.g. the heat sink body 402 of the secondary heat sink. The electrically conductive element 600 may be coupled and / or electrically connected to the secondary heat sink in one or more positions by virtue of the interference connector portions 606 being received within the interference fit bores 402d

[0068] As depicted, the interference connector portions 606 may depend from the plate portion 606 at one or more locations around the outside edge of the electrically conductive element 600, e.g. the plate portion 602. The interference connector portions 606 may extend at an angle, e.g. perpendicular, to the plane of the plate portion.

[0069] The interference connector portions 606 may extend from the plate portion 602 in a direction with a component opposite the direction in which the contacting portions 604 extend away from the plate portion 602.

[0070] As illustrated in Figure 8, the interference connector portions 606 may be configured to deform in order to be received within the interference fit bores 402d formed in the secondary heat sink. The interference connector portions 606 may comprise a hole 606a through the interference connector portions 606, e.g. through the sheet of material forming the interference connector portions 606. For example, the interference connector portions 606 may be oval shaped portions of sheet material, e.g. metal, having a central, e.g. oval shaped, hole. The interference connector portions 606 may be deformed, and the hole 606a may be at least partially collapsed in order for the interference connector portions 606 to be received within the interference fit bores 402d. The interference connector portions 606 may be resilient, and hence, the interference fit may be maintained between the interference connector portions 606 and the interference fit bores 402d by virtue of the resilience of the connector portions 606. In other arrangements, the interference connector portions 606 and interference fit bores 402d may be configured in any other way to enable the electrically conductive element to be coupled to the secondary heat sink.

[0071] Although in the arrangement depicted in Figures 6 to 9, the electrically conductive element 600 is a single electrically conductive element which contacts the main heat sink in a plurality of positions around the opening 302c. In other arrangements, the secondary heat sink assembly 500 may comprise a plurality of electrically conductive elements spaced around the heat sink body 402 to contact the main heat sink in the plurality of positions around the opening, e.g. respectively. Although not depicted in Figures 6 to 9, the secondary heat sink assembly 500 may comprise a seal, such as a deformable seal, made, for example, from a plastic, e.g. rubber material. The seal may be configured to seal between the main heat sink 302 and the secondary heat sink 400 around the opening 302c when the secondary heat sink assembly 500 is provided in the apparatus 300 described above, so as to prevent or restrict a flow of air between the main heat sink and secondary heat sink, e.g. through the opening. For example, the seal may comprise a gasket. The seal / gasket may be provided so as to contact the substantially planar portion of the heat sink body 402a of the secondary heat sink, e.g. around the heat dissipation fins 404. For example, the seal / gasket may be provided on an opposite side of the electrically conductive element 600 from the heat sink body 402. Alternatively, the seal / gasket may be arranged around outside or inside of the electrically conductive element relative to the heat dissipation fins. In other words, the seal / gasket may be provided between the heat dissipation fins and the electrically conductive element or the electrically conductive element may be provided between the heat dissipation fins and the seal.

[0072] With reference to Figure 10a, 10b, 11a and 11 b, a main heat sink 1000, e.g. for the apparatus 300, according to arrangements of the present disclosure will now be described. The main heat sink 1000 may be provided as part of the apparatus 300, e.g. in place of the main heat sink 302. The features described in relation to the main heat sink 302 may equally apply to the main heat sink 1000 and vice versa.

[0073] As described above with reference to the heat sink 302, the heat sink 1000 may comprise a heat sink body 1002 and a plurality of heat dissipation fins 1004. The heat sink body 1002 may be substantially planar, e.g. in the form of a plate. The heat dissipation fins 1004 may project from the plate portion on a first side 1002a of the plate. The dissipation fins 1004 may project from the plate portion in a direction at an angle, e.g. perpendicular, to the first side of the plate. As illustrated, the heat dissipation fins may be regularly, or evenly, spaced over the plate 1002 and may extend over the plate of the main heat sink in a principal direction, which may be referred to as a longitudinal direction DLof the heat sink 1000. The longitudinal direction may be aligned, e.g. parallel with the direction in which the flow of air flows through the air flow channels 352 defined by the housing 350, when the heat sink 1000 is provided within the apparatus 300 described above. The heat dissipation fins 1004 may extend across the plate parallel with one another. As depicted in Figures 10a and 10b, the heat sink 1000 comprises a plurality of openings 1006 through the heat sink for receiving a plurality of the secondary heat sinks 400, which may be provided as part of the secondary heat sink assembly 500. The openings 1006 may be spaced apart from one another across the heat sink 1000. The openings may be spaced apart in a lateral direction of the heat sink, perpendicular to the longitudinal direction DL. In other words, the openings 1006 may be spaced apart from one another in a direction perpendicular to the principal direction in which the heat dissipation fins 1004 of the main heat sink extend. The openings 1006, e.g. each of the openings, may be at least partially or substantially aligned with a cage for receiving a signal connector provided within the apparatus 300, e.g. when the main heat sink 1000 is provided within the apparatus 300. In some examples, the openings 1006 are open to an edge of the heat sink 1000.

[0074] The heat sink 1000 may further comprise one or more secondary heat sink seating portions 1010 which project over the openings 1006 in the heat sink 1000. The secondary heat sink seating portions may be for engaging the secondary heat sink 400 provided in the opening 1006 for locating the secondary heat sink 400, for example, in the direction through the opening. Additionally, when the electrically conductive element 600 and / or the seal are provided between the main and secondary heat sinks around the opening 1006, the secondary heat sink seating portions 1010 may be configured such that the electrically conductive element 600 and / or the seal are provided between secondary heat sink and the secondary heat sink seating portions.

[0075] As depicted, the secondary heat sink seating portions may project over the opening on either lateral side of the opening and a longitudinal end of the opening. As illustrated, an opposite longitudinal end of the opening may be at an edge of the pate 1002 of the main heat sink, and hence, a secondary heat sink seating portion may not be provided.

[0076] A seating surface 1010a of the secondary heat sink seating portions facing the opening 1006 may be aligned with or spaced apart from the first side 1002a of the heat sink body of the main heat sink on the same side of the opening. In this way, the heat sink body of the secondary heat sink can be received within the opening 1006 and be at least partially aligned with the heat sink body 1002 of the main heat sink in a direction through the opening 1006. In some examples, the main heat sink 1OOO is connected to the one or more secondary heat sink 400. In some aspects, the connection between the main heat sink 1000 and the one or more secondary heat sink 400 provides for a seal against airflow and / or dust passing between the main heat sink 1000 and the separate one or more secondary heat sinks 400. In a further aspect, the connection between the main heat sink 1000 and the one or more secondary heat sink 400 provides for an electrical connection. In some examples, a surface, e.g. a peripheral surface of the secondary heat sink 400 contacts the main heat sink 1000, e.g. against the secondary heat sink seating portions 1010. In some aspects, the secondary heat sink seating portions 1010 are configured to engage with the electrically conductive element 600. In some examples, a seal / gasket is located between the main heat sink 1000 and the one or more secondary heat sink 400.

[0077] In some aspects, the main heat sink 1000 is separately made and / or independent of one or more secondary heat sink 400. This allows for the design of the heat sinks to be optimised for each purpose, e.g. the secondary heat sink 400 may have a higher fin density than the main heat sink.

[0078] As illustrated, gaps 1012 may be provided between the secondary heat sink seating portions 1010 formed on either lateral sides of the openings. As shown in Figure 11 b, the gaps may be configured, e.g. sized and positioned, to correspond to the positions of the clips 522 and body part 526 of the resiliently deformable clip 520, so that resiliently deformable clip does not clash with the secondary heat sink seating portions when the apparatus 300 is assembled and when the resiliently deformable clip 520 is deformed in use of the apparatus.

[0079] As shown in Figure 10b, the main heat sink 1000 may comprise a wall 1020 extending at least partially around the opening or openings 1006. The wall projects in an opposite direction from the heat dissipation fins, e.g. inwardly, so that the wall projecting into the internal space 306 of the apparatus, e.g. so as to extend at least partially around the secondary heat sink 400 received within the opening. As shown in Figure 10a, the walls may also extend outwardly from the first side of the heat sink body, e.g. in the same directions as the heat dissipation fins, along one or more sides of the opening. For example, the walls 1020 may extend outwardly from the first side of the heat sink along the latera sides of the openings. The secondary heat sink seating portions may project from the walls 1020 over the openings. Further, as illustrated in Figure 10a, parts of the heat dissipation fins may be project from the walls 1020 in areas of the plate 1002 where the walls are provided.

[0080] As shown in Figure 11 b, when the apparatus 300 is assembled, the heat dissipation fins 404 of the secondary heat sinks received within the openings 1006 may extend principally across the heat sink bodies 402 of the secondary heat sinks in directions substantially parallel with the directions in which the heat dissipation fins 1004 principally extend across the heat sink body 1002 of the main heat sink. Accordingly, the heat dissipation fins 404 of the secondary heat sinks may be aligned or parallel with the direction of flow within the air flow channels 452.

[0081] The heat dissipation fins 404 of the secondary heat sinks may be narrower in the lateral direction of the main heat sink. Additionally or alternative, a pitch between the heat dissipation fins 404 of the secondary heat sinks may be smaller than the pitch between the heat dissipation fins 1004 of the main heat sink 1000 so that a greater number of heat dissipation fins 404 are provided on the secondary heat sink than are provided on the main heat sink in a similar sized area.

[0082] With reference to Figures 12a, 12b and 12c, an alternative arrangement of the apparatus 1200 will now be described. The apparatus 1200 depicted in Figures 12a, 12b and 12c may be similar to the apparatus 300 described above and the features described in relation to the apparatus may equally apply to the apparatus 1200.

[0083] The apparatus 1200 differs from the apparatus 300 in that the electrically conductive elements and the seal / gasket are not provided between the main heat sink 1000 and the secondary heat sink at the opening. Instead, one or more deformable electrically conductive seals 1202, 1204, 1206 are provided between the secondary heat sink 400 and the main heat sink 1000 at the openings 1006, in order to electrically connect the secondary heat sink to the main heat sink at one or more point or substantially continuously around the opening and to prevent or restrict a flow of air from passing through the opening, e.g. between the main heat sink and the secondary heat sink. In some arrangements, deformable electrically conductive seals 1202, 1204, 1206 may comprise a deformable material, such as plastic, e.g. rubber, coated or wrapped in an electrically conductive material, such as metal, e.g. metal wires or a metal mesh.

[0084] As shown in Figures 12a, 12b and 12c, the electrically conductive seals 1202, 1204, 1206 may be at least partially aligned with the heat sink body 402 of the secondary heat sink, in a direction through the openings 1006. The electrically conductive seals 1202, 1204, 1206 may be in contact with lateral side surfaces and optionally a longitudinal end surface of the plate portion 402a of the heat sink body of the secondary heat sink. As illustrated, when the apparatus 1200 is assembled, the electrically conductive seals 1202, 1204, 1206 may be disposed between the heat sink body 402 of the secondary heat sink and the walls 1020 of the main heat sink 1000, which extend around the heat sink body.

[0085] As shown, a cross-sectional shape of the electrically conductive seals 1202, 1204, 1206 may comprise a pair of lobe shaped arms 1212, 1214 connected together at one end of each of the arms at an angle join 1216, e.g. forming an acute or perpendicular angle relative to one another. In other words, the electrically conductive seals 1202, 1204, 1206 may be substantially “L” or “V” shaped in cross section. In the arrangement shown, the electrically conductive seals 1202, 1204, 1206 are oriented such that the lobes 1212, 1214 of their cross-sectional shape extend from the join 1216 between them in a direction towards the first side 1002a of the main heat sink, e.g. out of the internal space of the apparatus. However, in other arrangements, the electrically conductive seals 1202, 1204, 1206 may be arranged in a different orientation. For example, the lobes of their cross-sectional shape may extend from the join between them away from the opening, e.g. further into the internal space of the apparatus. In other arrangements, the electrically conductive seals 1202, 1204, 1206 may have any other cross-sectional shape. For example, the electrically conductive seals 1202, 1204, 1206 may have a substantially circular, square, oval or rectangular cross-sectional shape.

[0086] It will be appreciated by those skilled in the art that although the invention has been described by way of example, with reference to one or more exemplary examples, it is not limited to the disclosed examples and that alternative examples could be constructed without departing from the scope of the invention as defined by the appended claims.

[0087] Embodiment 1. An apparatus for telecommunications equipment, wherein the apparatus comprises: a main heat sink, wherein the main heat sink is configured to be in thermal contact with processing circuitry; and one or more secondary heat sinks, wherein the one or more secondary heat sinks are thermally coupled to a cage configured to receive a signal connector; wherein the main heat sink and the one or more secondary heat sink are connected.

[0088] Embodiment 2. The apparatus of embodiment 1 , wherein the main heat sink comprises a heat sink body, arranged to be in thermal contact with the processing circuitry, wherein the main heat sink further comprises an opening through the heat sink body, wherein the secondary heat sink is received within the opening in the main seat sink.

[0089] Embodiment 3. The apparatus of embodiment 1 or 2, wherein the secondary heat sink comprises a heat sink body thermally coupled with the cage and / or signal connector.

[0090] Embodiment 4. The apparatus of any of the preceding embodiments, wherein the apparatus further comprises a seal provided between the main heat sink and the secondary heat sink.

[0091] Embodiment 5. The apparatus of embodiment 4, wherein the seal comprises a gasket.

[0092] Embodiment 6. The apparatus of any of the preceding embodiments, wherein the apparatus further comprises one or more electrically conductive elements arranged between the main heat sink and the secondary heat sink, wherein the one or more electrically conductive elements are configured to electrically connect the main heat sink and the secondary heat sink at one or more locations, in order to improve electromagnetic shielding of the signal connector.

[0093] Embodiment 7. The apparatus of any of embodiment 4 or 5, wherein the seal is electrically conductive and is configured to electrically connect the main heat sink and the secondary heat sink at one or more locations, in order to improve electromagnetic shielding of the signal connector.

[0094] Embodiment 8. The apparatus of the preceding embodiments, wherein the apparatus comprises a plurality of cages configured to receive the signal connectors.

[0095] Embodiment 9. The apparatus of embodiment 8, wherein the main heat sink is arranged to be in thermal contact with signal connectors provided in one or more of the cages, e.g. via one or more (respective) thermal pads and / or signal connector heat sinks.

[0096] Embodiment 10. The apparatus of embodiment 9 and 2, wherein the opening in the main heat sink is at least partially aligned with another of the plurality of cages.

[0097] Embodiment 11. The apparatus of embodiment 10, wherein the heat sink body of the secondary heat sink is arrangeable to be in thermal contact, e.g. direct thermal contact, with another a signal connector received within the other of the cages.

[0098] Embodiment 12. The apparatus of any of the preceding embodiments, wherein a pitch of the heat dissipation fins of the secondary heat sink is smaller than a pitch of the heat dissipation fins of the main heat sink.

[0099] Embodiment 13. The apparatus of any of the preceding embodiments, wherein the main heat sink comprises a wall extending at least partially around the secondary heat sink.

[0100] Embodiment 14. The apparatus of embodiment 2 or any of embodiments 3 to 13 when depending on embodiment 2, wherein the main heat sink comprises one or more secondary heat sink seating portions projecting over the opening for restricting movement of the secondary heat sink through the opening. Embodiment 15. The apparatus of embodiment 2 or any of embodiments 3 to 14 when depending on embodiment 2, wherein the main heat sink comprises a plurality of the openings spaced apart from one another over the main heat sink, wherein the apparatus comprises a plurality of the secondary heat sinks receivable within respective ones of the openings in the main heat sink.

[0101] Embodiment 16. The apparatus of any of the preceding embodiments, wherein the apparatus further comprises a housing configured to define an air flow channel, wherein heat dissipation fins of the main heat sink and the secondary heat sink are arranged at least partially within with air flow channel.

[0102] Embodiment 17. A main heat sink for an apparatus for telecommunications equipment, wherein the main heat sink comprises a heat sink body, arranged to be in thermal contact with processing circuitry and an opening through the heat sink body, the opening for receiving a secondary heat sink such that the secondary heat sink is thermally coupled to a cage configured to receive a signal connector and is connected to the main heat sink.

[0103] Embodiment 18. A secondary heat sink for an apparatus for telecommunications equipment, wherein the apparatus comprises a main heat sink comprising an opening through the heat sink, wherein the secondary heat sink comprises a heat sink body and is receivable within the opening in the main seat sink, such that the heat sink body is in thermal contact with a cage configured to receive a signal connector.

[0104] Embodiment 19. A secondary heat sink assembly for an apparatus for telecommunications equipment, the secondary heat sink assembly comprising: a cage for receiving a signal connector, wherein the cage comprises an interface surface and an opening formed in the interface surface; and the secondary heat sink of embodiment 13, wherein the heat sink body of the secondary heat sink comprises a thermal contact portion configured to extend through the opening in the interface surface of the cage for contacting, e.g. directly contacting, the signal connector inside the cage. Embodiment 20. The secondary heat sink assembly of embodiment 19, wherein the secondary heat sink assembly further comprises a clip for resiliently coupling the secondary heat sink to the cage.

[0105] Embodiment 21 . The secondary heat sink assembly of embodiments 19 or 20, wherein the secondary heat sink assembly further comprises an electrically conductive element provided on an opposite side of the heat sink body from the cage, the electrically conductive element for contacting the main heat sink at one or more points around the opening through the main heat sink to electrically connect the secondary heat sink to the main heat sink at the one or more points.

[0106] Embodiment 22. The secondary heat sink assembly of embodiment 21 , wherein the electrically conductive element is resilient deformable between the secondary heat sink and the main heat sink, wherein the electrically conductive element is configured to seal the opening between the secondary heat sink and the main heat sink to prevent or restrict air and / or dust from passing through the opening.

[0107] Embodiment 23. The secondary heat sink assembly of embodiments 19 to 21 , wherein the assembly further comprises a seal element provided on an opposite side of the heat sink body from the cage, the seal element for contacting the main heat sink around the opening and configured to seal the opening between the secondary heat sink and the main heat sink to prevent or restrict air and / or dust from passing through the opening.

Claims

CLAIMS1. An apparatus for telecommunications equipment, wherein the apparatus comprises: a main heat sink, wherein the main heat sink is configured to be in thermal contact with processing circuitry; and one or more secondary heat sinks, wherein the one or more secondary heat sinks are thermally coupled to a cage configured to receive a signal connector; wherein the main heat sink is separate to the one or more secondary heat sink.2 The apparatus as claimed in claim 1 , wherein the main heat sink and the one or more secondary heat sinks have different thermal characteristics.

3. The apparatus as claimed in any one of the preceding claims, wherein the main heat sink and the one or more secondary heat sinks comprise heat dissipation fins, wherein a pitch of the heat dissipation fins of the secondary heat sink is smaller than a pitch of the heat dissipation fins of the main heat sink.

4. The apparatus as claimed in any one of the preceding claims, wherein the main heat sink and the one or more secondary heat sink are connected.

5. The apparatus as claimed in any one of the preceding claims, wherein the main heat sink and the one or more secondary heat sink are connected to provide for an electrical connection.

6. The apparatus as claimed in any one of the preceding claims, wherein the apparatus further comprises a seal provided between the main heat sink and the secondary heat sink.

7. The apparatus as claimed in claim 6, wherein the seal comprises a gasket.

8. The apparatus of any one of the preceding claims, wherein the apparatus further comprises one or more electrically conductive elements arranged between the main heat sink and the secondary heat sink, wherein the one or more electrically conductive elements are configured to electrically connect the main heat sink and thesecondary heat sink at one or more locations to provide electromagnetic shielding of the signal connector.

9. The apparatus of any one of the preceding claims, wherein the apparatus comprises a plurality of cages configured to receive the signal connectors.

10. The apparatus as claimed in any one of the preceding claims, wherein the main heat sink comprises a heat sink body, arranged to be in thermal contact with the processing circuitry, wherein the main heat sink further comprises an opening through the heat sink body, wherein the secondary heat sink is received within the opening in the main seat sink.

11. The apparatus as claimed in claim 10, wherein the main heat sink comprises one or more secondary heat sink seating portions projecting over the opening for restricting movement of the secondary heat sink through the opening.

12. The apparatus as claimed in claim 10 or claim 11 , wherein the main heat sink comprises a plurality of the openings spaced apart from one another over the main heat sink, wherein the apparatus comprises a plurality of the secondary heat sinks receivable within respective ones of the openings in the main heat sink.

13. The apparatus as claimed in any one of the preceding claims, wherein the apparatus further comprises a housing configured to define an air flow channel, wherein heat dissipation fins of the main heat sink and the secondary heat sink are arranged at least partially within with air flow channel.

14. A main heat sink for an apparatus for telecommunications equipment, wherein the main heat sink comprises a heat sink body, arranged to be in thermal contact with processing circuitry and further comprises an opening through the heat sink body, the opening configured to receive a separate secondary heat sink such that the secondary heat sink is thermally coupled to a cage configured to receive a signal connector.

15. A secondary heat sink for an apparatus for telecommunications equipment, wherein the apparatus comprises a separate main heat sink comprising anopening through the main heat sink, wherein the secondary heat sink comprises a heat sink body and is receivable within the opening in the separate main seat sink, such that the heat sink body is in thermal contact with a cage configured to receive a signal connector.

16. A secondary heat sink assembly for an apparatus for telecommunications equipment, wherein the apparatus comprises a separate main heat sink, the secondary heat sink assembly comprising: a cage for receiving a signal connector, wherein the cage comprises an interface surface and an opening formed in the interface surface; and the secondary heat sink of claim 15, wherein the heat sink body of the secondary heat sink comprises a thermal contact portion configured to be in thermal contact with the signal connector inside the cage.

17. The secondary heat sink assembly of claim 16, wherein the secondary heat sink assembly further comprises a clip for resiliently coupling the secondary heat sink to the cage.

18. The secondary heat sink assembly of claim 16 or 17, wherein the secondary heat sink assembly further comprises an electrically conductive element configured to contact the main heat sink at one or more points around the opening through the main heat sink to electrically connect the secondary heat sink to the main heat sink at the one or more points.

19. The secondary heat sink assembly of claim 18, wherein the electrically conductive element is resilient deformable between the secondary heat sink and the main heat sink, wherein the electrically conductive element is configured to seal the opening between the secondary heat sink and the main heat sink to prevent or restrict air and / or dust from passing through the opening.

20. The secondary heat sink assembly of claims 16 to 19, wherein the assembly further comprises a seal element provided on an opposite side of the heat sink body from the cage, the seal element for contacting the main heat sink around the opening and configured to seal the opening between the secondary heat sink and the main heat sink to prevent or restrict air and / or dust from passing through the opening.

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