Apparatus, system and method for supporting a field-replaceable unit in a telecommunications device via

Abstract

Embodiments of the present disclosure relate to apparatuses, systems, and methods for supporting field replaceable units in telecommunications equipment via retractable rails. The disclosed apparatus may include (1) a retractable guide rail movably coupled to the chassis, where the retractable guide rail is configured to support the field replaceable unit when the field replaceable unit is installed in the chassis, (2) a support bracket coupled to the chassis and aligned with the retractable guide rail within the chassis, and (3) a locking bracket movably coupled to the support bracket, where the locking bracket is configured to lock the field replaceable unit within the chassis. Wherein the locking bracket is configured to (A) engage the retractable guide rail in the deployed position when the field replaceable unit is not installed in the chassis, and (B) disengage the retractable guide rail such that the retractable guide rail moves to the retracted position when the field replaceable unit is installed in the chassis. Various other apparatuses, systems, and methods are also disclosed.

Description

[0001] This application is a divisional application of the invention patent application with the application date of November 3, 2021, application number 202111295639.3, and invention name “Device, system and method for supporting field replaceable units in telecommunications equipment via retractable guide rails”. Background Art

[0002] Field replaceable units (FRUs), such as line cards, are often heavy and / or bulky due, at least in part, to their size, dimensions, density, and / or components. Consequently, it can be difficult for administrators and / or technicians to install or uninstall the FRUs in telecommunications equipment, such as router racks and / or chassis.

[0003] Furthermore, recent performance demands and / or advancements have led manufacturers and / or suppliers to shorten the support channels of FRUs to accommodate additional electronic devices and / or components. Unfortunately, the shortening of these support channels may complicate the installation and uninstallation process for administrators and / or technicians when aligning the shortened support channels with corresponding guide rails in the telecommunications equipment, and / or may place a greater physical strain on the administrators and / or technicians carrying the weight of the FRUs from the telecommunications equipment.

[0004] Accordingly, the present disclosure identifies and addresses the need for additional and improved apparatuses, systems, and methods for supporting FRUs in telecommunications equipment via retractable rails. Summary of the Invention

[0005] As will be described in more detail below, the present disclosure generally relates to apparatus, systems, and methods for supporting a FRU in telecommunications equipment via retractable rails. In one example, an apparatus for accomplishing such a task may include (1) a retractable rail movably coupled to a chassis, wherein the retractable rail is configured to support the FRU when the FRU is installed in the chassis, (2) a support bracket coupled to the chassis and aligned with the retractable rail within the chassis, and (3) a locking bracket movably coupled to the support bracket, wherein the locking bracket is configured to (A) engage the retractable rail in an extended position within the chassis when the FRU is not installed in the chassis, and (B) disengage the retractable rail when the FRU is installed in the chassis, causing the retractable rail to move to a retracted position.

[0006] Similarly, a system for accomplishing such a task can include (1) a chassis, (2) a retractable rail movably coupled to the chassis, wherein the retractable rail is configured to support a FRU when the FRU is installed in the chassis, (3) a support bracket coupled to the chassis and aligned with the retractable rail within the chassis, and (4) a locking bracket movably coupled to the support bracket, wherein the locking bracket is configured to (A) engage the retractable rail in an extended position within the chassis when the FRU is not installed in the chassis, and (B) disengage the retractable rail when the FRU is installed in the chassis such that the retractable rail moves to a retracted position within the chassis.

[0007] A corresponding method can include (1) movably coupling a retractable rail to a chassis of a telecommunications device such that the retractable rail is configured to support a FRU when the FRU is installed in the chassis, (2) coupling a support bracket to the chassis such that the support bracket is aligned with the retractable rail within the chassis of the telecommunications device, and (3) movably coupling a locking bracket to the support bracket such that the locking bracket is configured to (A) engage the retractable rail in an extended position within the chassis when the FRU is not installed in the chassis, and (B) disengage the retractable rail when the FRU is installed in the chassis such that the retractable rail moves to a retracted position within the chassis.

[0008] The features of any of the above embodiments can be used in combination with each other in accordance with the general principles described herein. These and other embodiments, features, and advantages will be more fully understood in view of the following detailed description, in connection with the claims and the appended drawings. BRIEF DESCRIPTION OF DRAWINGS

[0009] The accompanying drawings illustrate a number of example embodiments and are a part of the specification. Together with the following description, these drawings demonstrate and explain various principles of the disclosure.

[0010] Figure 1 is an illustration of an example apparatus for supporting a FRU in a telecommunications device via a retractable rail in accordance with one or more embodiments of the present disclosure;

[0011] Figure 2 is an additional illustration of an example apparatus for supporting a FRU in a telecommunications device via a retractable rail in accordance with one or more embodiments of the present disclosure;

[0012] Figure 3 is an additional illustration of an example apparatus for supporting a FRU in a telecommunications device via a retractable rail in accordance with one or more embodiments of the present disclosure;

[0013] Figure 4 is an additional illustration of an example apparatus for supporting a FRU in a telecommunications device via a retractable rail in accordance with one or more embodiments of the present disclosure;

[0014] Figure 5 is an additional illustration of an exemplary apparatus for supporting a FRU in telecommunications equipment via a retractable rail according to one or more embodiments of the present disclosure;

[0015] Figure 6 is an illustration of an exemplary telecommunications device including a retractable rail for supporting a FRUS according to one or more embodiments of the present disclosure;

[0016] Figure 7 is a diagram of an exemplary FRU according to one or more embodiments of the present disclosure;

[0017] Figure 8 is an additional illustration of an exemplary telecommunications device including a retractable rail for supporting a FRUS according to one or more embodiments of the present disclosure;

[0018] Figure 9 is an illustration of an exemplary chassis including retractable rails for supporting a FRUS according to one or more embodiments of the present disclosure;

[0019] Figure 10 is an additional illustration of an exemplary telecommunications device including a retractable rail for supporting a FRUS according to one or more embodiments of the present disclosure; and

[0020] Figure 11 is a flow chart of an exemplary method for assembling an apparatus for supporting a FRU in telecommunications equipment according to one or more embodiments of the present disclosure.

[0021] Throughout the drawings, the same reference numerals and descriptions denote similar, but not necessarily identical, elements. Although the exemplary embodiments described herein are susceptible to various modifications and alternative forms, specific embodiments have been shown in the drawings by way of example and will be described in detail herein. However, the exemplary embodiments described herein are not intended to be limited to the specific forms disclosed. On the contrary, this disclosure encompasses all modifications, equivalents, and alternatives falling within the scope of the appended claims. DETAILED DESCRIPTION

[0022] The present disclosure describes various devices, systems, and methods for supporting a FRU in a telecommunications device via retractable rails. As will be explained in more detail below, embodiments of the present disclosure may include and / or relate to retractable rails, support brackets, and / or locking brackets that are collectively configured within a chassis, such that the locking brackets (1) engage the retractable rails in an extended position when the FRU is not installed, and / or (2) disengage the retractable rails when the FRU is installed to facilitate moving the retractable rails to a retracted position. This configuration of the retractable rails, support brackets, and / or locking brackets may assist an administrator and / or technician in installing and / or uninstalling a FRU within a chassis of the telecommunications device by reducing and / or alleviating his or her physical burden (e.g., when aligning with shortened support channels on the FRU side panels during installation, and / or when bearing the weight of the FRU during uninstallation).

[0023] refer to Figures 1-10 , the following provides a detailed description of exemplary components, devices, systems, configurations and / or implementations for supporting FRUs in telecommunications equipment via retractable rails. Figure 11 The corresponding discussion will provide a detailed description of an exemplary method for assembling and / or manufacturing an apparatus for supporting a FRU in telecommunications equipment via retractable rails.

[0024] Figure 1-Figure 5 An exemplary apparatus 100 for supporting a FRU in telecommunications equipment is shown. Figure 1-Figure 5 As shown, the exemplary apparatus 100 may include and / or represent a retractable rail 102, a support bracket 104, and a locking bracket 106. In some examples, the retractable rail 102 may be movably coupled to the chassis (not necessarily in the Figure 1-Figure 5 ). In these examples, the support bracket 104 can be fixedly coupled to the chassis and / or aligned with the retractable rail 102 within the chassis. In one example, the locking bracket 106 can be movably coupled to the support bracket 104. In this example, the locking bracket 106 can be configured, assembled, and / or designed to engage the retractable rail 102 in an extended position within the chassis when a FRU is not installed in a corresponding slot of the chassis. Additionally or alternatively, the locking bracket 106 can be configured, assembled, and / or designed to disengage the retractable rail 102 when a FRU is installed in a corresponding slot of the chassis, causing the retractable rail 102 to move and / or return to a retracted position.

[0025] like Figure 1-Figure 5As shown, the retractable rail 102 can include and / or form one or more slots, such as slots 108(1), 108(2), and / or 108(3). In some examples, the slots 108(1)-(3) can house brackets that attach to the chassis and / or enable the retractable rail 102 to move back and forth across a portion of the chassis between the extended position and the retracted position. In such examples, the slots 108(1)-(3) can define a distance and / or length that the retractable rail 102 is able to move between the extended position and the retracted position. Additionally or alternatively, the brackets can pass through the slots 108(1)-(3) to movably couple the retractable rail 102 to the chassis. These brackets can provide stability and / or support to the retractable rail 102 while also enabling the retractable rail 102 to move back and forth loosely between the extended position and the retracted position. Thus, these brackets can provide a slight spatial buffer for movement of the retractable rail 102.

[0026] In some examples, the device 100 can include and / or incorporate a spring 110 that is coupled between the retractable rail 102 and the chassis or an extension of the chassis (e.g., a bracket, a screw, a pin, etc.). In such examples, the spring 110 can be configured, applied, and / or designed to move and / or return the retractable rail 102 to the extended position when an FRU is not installed in the corresponding slot of the chassis. In other words, the spring 110 can apply, exert, and / or deliver a force that causes the retractable rail 102 to move or return to the extended position when an FRU is not installed in the corresponding slot of the chassis. Thus, the retractable rail 102 can be spring-loaded.

[0027] The retractable rail 102, the support bracket 104, and / or the locking bracket 106 can each be dimensioned in any manner to fit within a designated area of the chassis and / or interface with or support a certain FRU. Additionally or alternatively, the retractable rail 102, the support bracket 104, and / or the locking bracket 106 can each include and / or comprise any of a variety of materials (e.g., metal) to support and / or hold a certain FRU.

[0028] As shown in at least one of the figures in Figure 2-Figure 4 In some examples, the pin 210 can couple and / or attach the rod 212 to the support bracket 104. In such examples, the spring 208 can extend and / or protrude from the rod 212. Additionally or alternatively, the spring 208 can press against and / or abut a wall of the chassis. Thus, the locking bracket 106 can be spring-loaded.

[0029] In some examples, the lever 212 can be configured, assembled, and / or designed to pivot, rock, and / or move about or around the pin 210. For example, when an FRU is installed and / or inserted into a slot configured with the appliance 100, the FRU can depress the back end of the locking bracket 106, causing the lever 212 to pivot, rock, and / or move about the pin 210 to disengage the retractable guide rail 102. The depression of the FRU can compress and / or load the spring 208. When the lever 212 disengages the retractable guide rail 102, the spring 110 can cause the retractable guide rail 102 to retract and / or fold into the support bracket 104 in the retracted position. In other words, the spring 110 can pull the retractable guide rail 102 back to rest against the support bracket 104 when the lever 212 disengages the retractable guide rail 102.

[0030] Additionally or alternatively, when an FRU is unloaded and / or removed from a slot configured with the appliance 100, the FRU can release the back end of the locking bracket 106 and / or pull or draw the retractable guide rail 102 to the extended position. The release of the back end of the locking bracket 106 by the FRU can activate, unload, and / or decompress the spring 208, causing the lever 212 to pivot, rock, and / or move about the pin 210 to engage the retractable guide rail 102 when pulled and / or drawn to the extended position. When the lever 212 engages the retractable guide rail 102, the retractable guide rail 102 can be held and / or maintained at a distance from the support bracket 104 in the extended position. In other words, the retractable guide rail 102 can prevent the retractable guide rail 102 from retracting and / or folding into the support bracket 104 when the lever 212 engages the retractable guide rail 102.

[0031] The springs 110 and 208 can each include and / or represent any type or form of spring mechanism and / or device for suitable purposes. In one example, the spring 110 can include and / or represent a tension spring designed to extend and / or expand the retractable guide rail 102 when no FRU is installed. Additionally or alternatively, the spring 208 can include and / or represent a flat and / or compression spring designed to push and / or hold the lever 212 away from the chassis wall when no FRU is installed. Examples of the springs 110 and 208 include, but are not limited to, a coil spring, a tension spring, a tension spring, a horse-shoe spring, a torsion spring, a compression spring, a leaf spring, a constant force spring, a gas spring, a combination or variation of one or more of them, and / or any other suitable spring.

[0032] Figure 6 An example telecommunications appliance 600 is shown that includes and / or represents a chassis 602, a midplane 604, and / or appliances 100(1), 100(2), and 100(3). As Figure 6As shown, devices 100(1)-(3) can be coupled to and / or mounted in chassis 602 via standoffs and / or screws. In some examples, devices 100(1)-(3) can be configured and / or arranged to support and / or maintain three different FRUs within chassis 602. In such an example, the paired device ( Figure 6 (not shown) may be configured and / or arranged on a side opposite to the devices 100(1)-(3) within the chassis 602. Each of the devices 100(1)-(3) may include and / or represent the above combination Figure 1-Figure 5 Any of the described components, parts and / or mechanisms.

[0033] In some examples, the midplane 604 can be configured and / or mounted in the chassis 602. In one example, when the FRU is installed and / or inserted into a slot equipped with one of the devices 100 (1)-(3), the FRU can depress the rear end of the corresponding locking bracket, thereby causing the corresponding rod to pivot, tilt and / or move to disengage the retractable rail. Since the rod is disengaged from the retractable rail in this example, the retractable rail can be retracted and / or folded toward the corresponding support bracket to a retracted position. In the retracted position, the retractable rail can abut the support bracket to enable the FRU to dock with and / or connect to the midplane 604. Conversely, when the FRU is unloaded and / or removed from the slot equipped with one of the devices 100 (1)-(3), the FRU can release the rear end of the locking bracket 106 and / or pull or extend the retractable rail 102 to the extended position.

[0034] In some examples, telecommunications device 600 may include and / or represent a router (e.g., a provider edge router, a hub router, a branch router, an autonomous system boundary router, and / or a regional boundary router) that receives, routes, forwards, and / or otherwise processes network traffic. Additional examples of telecommunications device 600 include, but are not limited to, switches, hubs, modems, bridges, repeaters, gateways, multiplexers, network adapters, network interfaces, client devices, desktops, servers, variations or combinations of one or more thereof, and / or any other suitable telecommunications equipment.

[0035] Figure 7 shows a device that can be installed and / or inserted into Figure 6 An exemplary FRU 700 in a slot of a telecommunications device 600 in FIG. Figure 7 As shown, the exemplary FRU 700 may include and / or represent a side panel 708. In some examples, the side panel 708 may include and / or form a channel 710 that is aligned with the side panel 708. Figure 6The retractable rails of one of the devices 100 (1)-(3) in the embodiment of the present invention may be docked with and / or engaged with the retractable rails of one of the devices 100 (1)-(3). In such an example, the retractable rails may apply, exert, and / or transmit forces on the channel 710 for supporting the FRU 700 when installed and / or inserted into a slot of the telecommunications equipment 600.

[0036] In some examples, the side panel 708 may contact and / or depress Figure 6 7. The FRU 700 may be configured to include a locking bracket of one of the devices 100(1)-(3) in the apparatus 700. For example, the bottom of the channel 710 may contact the locking bracket of one of the devices 100(1)-(3), thereby depressing the locking bracket. By doing so, the side panel 708 and / or the bottom of the channel 710 may cause the locking bracket to disengage the corresponding retractable rail, thereby causing and / or enabling the retractable rail to move and / or fold to a retracted position. Examples of the FRU 700 include, but are not limited to, a line card, a physical interface card (PIC), a flexible PIC concentrator (FPC), a switch interface board (SIB), a control board, a routing engine, a packet forwarding engine, a fan tray, a connector interface panel, portions of one or more thereof, combinations or variations of one or more thereof, and / or any other suitable FRU.

[0037] Figure 8 Another view of an exemplary telecommunications device 600 including and / or representing a chassis 602, a midplane 604, and / or apparatus 100(1)-(3) is shown. Figure 8 As shown, the device can be coupled to and / or mounted in chassis 602 to support and / or each other three different FRUs. Each of these devices can include and / or represent the above combination Figures 1-6 Any components, parts and / or mechanisms described.

[0038] Figure 9 An exemplary chassis 602 is shown with devices 100(1) and 100(2) and fixed short rails 902(1) and 902(2) mounted therein. Figure 9 As shown, the devices 100(1) and 100(2) can be intermixed and / or intermingled with the fixed short rails 902(1) and 902(2) in the chassis 602. However, unlike the fixed short rails 902(1) and 902(2), the devices 100(1) and 100(2) can provide certain support benefits to an administrator and / or technician installing and / or uninstalling a FRU. For example, the devices 100(1) and 100(2) can assist the administrator and / or technician in installing and / or uninstalling a FRU within the chassis 602 by reducing and / or relieving his or her physical burden (e.g., when aligning with the shortened support channels on the FRU side panels during installation, and / or when bearing the weight of the FRU during uninstallation).

[0039] Figure 10 An exemplary telecommunications device 600 is shown that includes and / or represents a chassis 602, a line card 1010, and a line card 1008. Figure 10 As shown, line cards 1010 can be installed and / or inserted into different slots of chassis 602. In some examples, because line cards 1010 are installed and / or inserted into those slots of chassis 602, the retractable rails applied to those slots can be folded to a retracted position. In contrast, line card 1008 can be uninstalled and / or not fully installed into its slot of chassis 602. Therefore, because line card 1008 is not fully installed into its slot of chassis 602, the retractable rails applied to that slot can be lengthened to enter an extended position.

[0040] Figure 11 is a flow chart of an exemplary method 1100 for assembling and / or manufacturing an apparatus for supporting a FRU in telecommunications equipment. The method 1100 may include step (1110). Step 1110 may be performed in a variety of ways, including in combination with the above. Figures 1-10 For example, a computing device manufacturer or subcontractor may movably couple and / or attach the retractable rails to a chassis of the telecommunications equipment such that the retractable rails are configured to support the FRU when the FRU is installed in the chassis.

[0041] Method 1100 may also include the step of coupling the support bracket to the chassis such that the support bracket is aligned with the retractable rail within the chassis of the telecommunications equipment (1120). Step 1120 may be performed in a variety of ways, including in combination with the above. Figures 1-10 For example, a computing device manufacturer or subcontractor may couple and / or secure the support bracket to the chassis such that the support bracket is aligned with the retractable rail within the chassis of the telecommunications equipment.

[0042] The method 1100 may further include the following steps (1130): movably coupling the locking bracket to the support bracket such that the locking bracket is configured to engage the retractable rail in the extended position when the FRU is not installed and disengage the retractable rail when the FRU is installed such that the retractable rail moves to the retracted position. Step 1130 may be performed in a variety of ways, including in combination with the above. Figures 1-10 For example, the computing device manufacturer or subcontractor may movably couple and / or attach the locking bracket to the support bracket such that the locking bracket is configured to engage the retractable rails in the extended position when the FRU is not installed and disengage the retractable rails when the FRU is installed, such that the retractable rails move to the retracted position.

[0043] Although the foregoing disclosure uses specific block diagrams, flow charts, and examples to illustrate various embodiments, each block diagram component, flow chart step, operation, and / or component described and / or illustrated herein may be implemented individually and / or collectively using various hardware, software, or firmware (or any combination thereof) configurations. Furthermore, any disclosure of components contained within other components should be considered exemplary in nature, as many other architectures may be implemented to achieve the same functionality.

[0044] The process parameters and step sequences described and / or illustrated herein are provided as examples only and may be modified as needed. For example, although the steps illustrated and / or described herein may be shown or discussed in a particular order, the steps do not necessarily need to be performed in the order shown or discussed. The various exemplary methods illustrated and / or described herein may also omit one or more of the steps illustrated and / or described herein, or include additional steps in addition to the steps disclosed.

[0045] The foregoing description has been provided to enable others skilled in the art to best utilize the various aspects of the exemplary embodiments disclosed herein. This exemplary description is not intended to be exhaustive or limited to any precise form disclosed. Many modifications and variations are possible without departing from the spirit and scope of the present disclosure. The embodiments disclosed herein should be considered in all respects as illustrative and not restrictive. Reference should be made to the appended claims and their equivalents when determining the scope of the present disclosure.

[0046] Unless otherwise indicated, the terms "connected to" and "coupled to" (and their derivatives) used in the specification and claims should be interpreted as allowing both direct and indirect (i.e., via other elements or components) connections. Furthermore, the terms "a" or "an" used in the specification and claims should be interpreted as meaning "at least one of..." Finally, for ease of use, the terms "including" and "having" (and their derivatives) used in the specification and claims are interchangeable with the word "comprising" and have the same meaning.

Claims

1. A device comprising: a retractable rail movably coupled to the chassis via one or more standoffs, wherein the retractable rail is configured to support a field replaceable unit when the field replaceable unit is installed in the chassis; a support bracket coupled to the chassis and aligned with the telescoping rail within the chassis; and a locking bracket movably coupled to the support bracket, wherein the locking bracket is configured to: engaging the retractable rails in an extended position within the chassis when the field replaceable unit is not installed in the chassis; and When the field replaceable unit is installed in the chassis, the retractable rails are disengaged so that the retractable rails move to a retracted position.

2. The device according to claim 1, wherein The telescopic rail includes one or more slots, and the bracket passes through the one or more slots to movably couple the telescopic rail to the chassis.

3. The apparatus of claim 2, further comprising a spring coupled between the retractable rail and the chassis or an extension of the chassis, wherein The spring is configured to move the telescoping rail to the deployed position when the field replaceable unit is not installed.

4. The device according to claim 3, wherein The locking bracket is further configured such that the field replaceable unit, when installed in the chassis, depresses the locking bracket to disengage the telescoping rail and enable the telescoping rail to move to the retracted position.

5. The device according to claim 4, wherein The field replaceable unit includes a side panel, the side panel: including a channel that interfaces with the retractable rail coupled to the chassis to support the field replaceable unit; as well as The locking bracket is depressed to disengage the telescoping rail and enable the telescoping rail to move to the retracted position.

6. The device according to claim 3, wherein The extension of the chassis includes a mount that movably couples the telescoping rail to one of the mounts of the chassis.

7. The device according to claim 2, wherein The slot defines a distance the telescoping rail can move between an extended position and a telescoping position.

8. The apparatus according to claim 1, wherein The support bracket includes a spring coupled to the locking bracket, wherein the spring causes the locking bracket to engage the telescoping rail in the deployed position when the field replaceable unit is not installed in the chassis.

9. The device according to claim 8, wherein The locking bracket includes a pin and a lever configured to pivot about the pin when the locking bracket is engaged or disengaged by the field replaceable unit.

10. The device according to claim 1, wherein The deployed position positions the telescoping rails toward the front of the chassis to support the field replaceable unit for installation into the chassis.

11. The device according to claim 1, wherein The retracted position causes the telescoping rail to abut the support bracket to enable the field replaceable unit to dock with the midplane of the chassis.

12. A telecommunications device comprising: Chassis; a retractable rail movably coupled to the chassis via one or more standoffs, wherein the retractable rail is configured to support a field replaceable unit when the field replaceable unit is installed in the chassis; a support bracket coupled to the chassis and aligned with the telescoping rail within the chassis; and a locking bracket movably coupled to the support bracket, wherein the locking bracket is configured to: engaging the retractable rails in an extended position within the chassis when the field replaceable unit is not installed in the chassis; and When the field replaceable unit is installed in the chassis, the retractable rails are disengaged so that the retractable rails move to a retracted position within the chassis.

13. The telecommunications device according to claim 12, wherein: The telescopic rail includes one or more slots, and the bracket passes through the one or more slots to movably couple the telescopic rail to the chassis.

14. The telecommunications device of claim 13, further comprising a spring coupled between the telescopic rail and the chassis or an extension of the chassis, wherein The spring is configured to move the telescoping rail to an extended position when the field replaceable unit is not installed.

15. A method comprising: movably coupling a telescoping rail to a chassis of telecommunications equipment via one or more standoffs, such that the telescoping rail is configured to support a field replaceable unit when the field replaceable unit is installed in the chassis; coupling a support bracket to the chassis such that the support bracket is aligned with the telescoping rail within the chassis of the telecommunications equipment; as well as The locking bracket is movably coupled to the support bracket such that the locking bracket is configured to: engaging the retractable rails in an extended position within the chassis when the field replaceable unit is not installed in the chassis; and When the field replaceable unit is installed in the chassis, the retractable rails are disengaged so that the retractable rails move to a retracted position within the chassis.

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