Abstract: A holder for protecting a palmtop comprising of an activation button. When the activation button is depressed, it shuts down the palmtop which is removed from the holder by pushing it forward along the holder. The activation button comprises of an embossment, a boss, contact point, and trigger. The embossment connects with the palmtop tightly before the activation button is depressed while the boss is convenient for users to press the activation button. Moreover, the contact point will touch the trigger to shut down the palmtop after the active button is depressed.

Abstract: An apparatus and method for activating a switch with a circuit board ejector includes a circuit board and a switch assembly including the switch for transitioning the circuit board from a first mode to a second mode and vice versa. The switch assembly is attached to the circuit board, and the circuit board ejector is rotatably attached to the circuit board to allow the circuit board ejector to be positioned in an unlatched position and a latched position. The circuit board ejector includes a hook portion and a bracket arm wherein the bracket arm of the circuit board ejector activates the switch assembly and causes the circuit board to transition from the first mode to the second mode and vice versa.

Abstract: A processor retention assembly is disclosed. An embodiment of the processor retention assembly includes a first dual processor retention module and a second dual processor retention module. A connecting member is attached to the first dual processor retention module at a first end and is attached to the second dual processor retention module at a second end. In accordance with another embodiment of the present invention, covers are hingedly attached to each of the first and second dual processor retention modules.

Abstract: The invention includes a latch assembly movably mounted on a module. The module is removably supportably on a chassis, and movement of the latch assembly with respect to the module aids in removal and installation thereof. The invention also includes a sensor mounted on the module and configured to detect the movement of the latch assembly through a first range. The latch assembly must be moved through a second range in order to move the module relative to the chassis. However, the latch assembly is moved through the first range prior to moving through the second range. Thus, the sensor can detect imminent movement of the module relative to the chassis by detecting movement of the latch assembly through the first range. The latch assembly can be configured to be secured in a given position so as to prevent inadvertent movement of the latch assembly. The invention also includes a method for removal of a module which is supported on a chassis.

Abstract: A door mechanism comprises a frame having an insertion port and first and second door panels. The first and second door panels have respective pivot shafts rotatably connected to the frame. These door panels are supported by the frame such that they can swing about the respective pivot shafts between closed positions in which they close the insertion port, and open positions in which they open the insertion port. The first and second door panels are swung apart in opposite directions when they are shifted from the respective closed positions to the respective open positions. The first and second door panels are urged by a spring toward the respective closed positions.

Abstract: The mechanism for inserting, extracting, sensing and locking a printed circuit board assembly (PCBA) in an electronic system provides both easier use and a longer service life for the PCBA as compared to a mechanism having two locking handles. Insertion, extraction, sensing and locking are simplified because a single handle can be used rather than two handles. The service life of the associated PCBA is extended because the forces applied to the PCBA are synchronous and applied more evenly than a PCBA having two handles, which reduces bending and other forces that can cause component failure.

Abstract: An electronically-enabled encasement for a handheld computer is provided. The encasement includes an encasement portion configured to cover at least a portion of the handheld computer, including a front surface of the handheld computer providing access to a display; a spine engageable with an accessory slot of the handheld computer to detachably couple the encasement with the handheld computer; a connector to electronically connect the encasement to the handheld computer; and at least one electronic component embedded in the encasement portion. The encasement may also include a wireless communication port such a radio frequency transmitter or an IR transceiver.

Abstract: A storage box for hard disk drive (HDD) is provided. The storage box includes an outer frame, a first holder, a second holder, a cooling module and a back panel board. The first and second holders are opposite and for supporting the HDD. The cooling module, for cooling the HDD, is fixed in the storage box via the second holder and the outer frame. The cooling air is drawn into the storage box by the cooling module. The back panel board is electrically connected to the cooling module. The back panel board has an outlet positioned relative to the cooling module. The cooling air is flowed through surface of the HDD and a heat sink of the cooling module, and then exhausted from the outlet of the back panel board.

Abstract: A switched communications device includes a multi-port jack housing having portions defining a plurality of recesses extending inwardly from the front for receiving respective mating plugs. Signal connectors are preferably positioned within each of the recesses and define respective communications ports. A circuit board is positioned within the multi-port jack housing and preferably extends adjacent the back. The switched communications device preferably includes at least one switched communications processor mounted on the circuit board and connected to the plurality of communications ports for processing inbound and outbound communications signals so that the signals are switched among the communications ports. A switched communications processor preferably communicates with two or more of the communications ports. The signal connectors may be electrical and/or optical, and may be compatible with an RJ-45 jack. An internal EMI shield may be provided in the circuit board.

Abstract: A stiffener supports a printed circuit board during insertion and removal within a slot of a card cage having one or more electrical connectors. The stiffener has a rigid elongated member that defines an elongated channel. The elongated member is adapted to engage an edge of the printed circuit board along the channel. The member has an engagement portion for receiving an applied force, a driver portion for engaging an electrical connecting mechanism, and a translator portion for translating the force from the engagement portion to the driver portion.

Abstract: A collapsible mount for mounting an electronic device to a circuit board includes a base adapted to be fixed to the circuit board and two support arms each having a lower end pivotably connected to the base and spaced from each other so as to be rotatable with respect to the base between a stowed position and an expanded position wherein the two support arms are substantially opposite to each other to define a space therebetween adapted to accommodate the electronic device therein.

Abstract: An ejection system for engaging a transceiver to a host circuit board in a guide rail having a front and back orientation and for ejecting said transceiver from said guide rail, said system comprising: (a) a latching mechanism within said guide rail adapted for latching to a projection extending from a housing of a transceiver when said transceiver is moved backward on said guide rail to an engaging position, thereby preventing said transceiver from moving forward; (b) resilient means within said guide rail adapted for urging said transceiver forward when said transceiver is in said engaging position; and (c) a release mechanism within said card guide and adapted for disengaging said latching mechanism from said projection when said release mechanism is actuated to a releasing position, thereby allowing said resilient means to move said transceiver forward.

Abstract: In a card ejecting device, when a card is slidingly inserted into a case-shaped holder up to a predetermined position, the card is connected to contacting portions of contacts attached to the holder, and a rear-end portion of the card is pushed in a forward directly by pressing portions of a slider which slides while being guided by the holder, so as to move the card up to a removing position. The pressing portions are formed by front end faces of pieces provided on the slider in such a manner as to extend in the direction in which the card is pressed. Spaces (notched portions) allowing the advance of the pressing portions during the advance of the slider are formed in the holder.

Abstract: A rotatable latch is provided for securing an object to a holder and for preventing unintended removal of the object. In a preferred embodiment, the rotatable latch has at least two actuators flexibly mounted to a body. Each actuator has a hooked portion which engages a portion of the holder. A lever portion may be provided for releasing the hooked portion. The hooked portion is rotated about a pivot point to release the object from the holder. Rotation occurs when actuators are released through use of at least two lever portions. To prevent accidental removal of the object, the second actuator cannot be released until the first actuator has been released. The latch requires at least two actions, pressing the levers in succession, to release the object. The invention is applicable, for example, to circuit packs for electronic circuit boards.

Abstract: A computer peripheral device with an integral ground clip. In one embodiment, the present invention includes a substrate. The substrate has a ground signal receptacle location coupled thereto. The present embodiment further includes an enclosure which adapted to be coupled to the substrate. In this embodiment, the enclosure has a conductive region coupled thereto. The enclosure further includes a grounding member which is integral therewith. The grounding member is disposed such that the grounding member is electrically coupled to the ground signal receptacle location when the enclosure is assembled to the substrate. In so doing, the present invention provides a computer peripheral device which, among other benefits, effectively dissipates ground signals.

Abstract: An ejector device for removing a mobile module from a main board includes a support frame and a lever. The support frame is secured on the main board so as to extend in a direction transverse to a plane of the main board, and is disposed adjacent to the mobile module. The lever includes an ejecting plate portion disposed between the main board and the mobile module, a connecting plate portion and an operating plate portion. The connecting plate portion extends from the ejecting plate portion, and is disposed between the support frame and the mobile module. The connecting plate portion is mounted pivotally on the support frame about an axis parallel to the plane of the main board. The operating plate portion extends from the connecting plate portion, and is operable to cause the connecting plate portion to pivot relative to the support frame and enable the ejecting plate portion to push the mobile module away from the main board.

Abstract: A data card having a retractable handle is disclosed. In the preferred embodiment, the data card includes an electronic data storage medium contained within a two-piece protective housing. A removable handle is slidably engaged with the housing and is movable between a stored position, wherein the handle does not extend beyond the housing, and an active position, wherein the handle is extended beyond the housing for easy manipulation by the user. In an alternative embodiment, the handle is pivotally mounted to the housing and is movable between a stored position, wherein the handle is maintained against the housing, and an active position, wherein the handle is pivotally swung away from the housing.

Abstract: In a card connector comprising a plurality of contacts at a rear end portion thereof to be mounted onto a printed circuit board, a card receiving portion in front of the contacts for receiving a card to be connected to said contacts, and an ejector mechanism for ejecting said card from connection with said contacts, the contacts are mounted in a thin insulator body to form a connector portion, while the card receiving portion is formed in a rectangular cylindrical frame portion which is mounted onto the connector portion after the connector portion is mounted onto a printed circuit board. The ejector mechanism is previously assembled onto the frame portion.

Abstract: A multilayer ceramic device has top and bottom green ceramic layers machined and fired. Intermediate green ceramic layers are machined, have conductors laid down in the machined areas, are laminated, and are fired to form an enclosure layer. The areas of the layers which will be in contact with each other are coated with a bonding agent. The layers are aligned and bonded to form a structure having arbitrarily shaped, interior channels adjacent to the top and bottom layers which are not subject to detrimental nonplanarities.

Abstract: A function of the extending apparatus for an information processing device including at least one connector provided on a surface of the function extending apparatus for mounting the information processing device, and connected with a corresponding connector provided on a lower surface of the information processing device, when the information processing device is mounted on the function extending apparatus. The function extending apparatus includes a pushing member moved in an upper direction so as to push the information processing device up from the function extending apparatus, a rotatable operation member, and a push-up mechanism which moves the pushing member in the upper direction, when the operation member is rotated.

Abstract: A tool-actuated ejector for extracting electronic modular components. The ejector, which functions as a levered cam, has a body with a first end, a second end and a pivot located intermediate the first and second ends. A tool-receiving socket mounts at the second end. A tool, such as a screwdriver with a blade that matches the shape of the socket, actuates the ejector by applying a force to the socket. A cam, located at the first end, engages the electronic modular component. To provide a mechanical advantage, the distance between the tool-receiving socket and the pivot, which constitutes one lever arm, is greater than the distance between the cam and the pivot, which constitutes a second lever arm. In addition, a shock absorber mounts on the body and gliders extend below the body to provide stability and balance to the ejector. The ejector mounts in a casing having a tool passage that communicates with the tool-receiving socket and the exterior of the casing.

Abstract: An expansion card retention system and method. In one embodiment, the expansion card retention system includes an expansion card retaining unit which has a vertical axis, an extended member, and a vertical-axis extended member pressure application device operably connected to the extended member. In another embodiment, a data processing system includes the expansion card retention system. In yet another embodiment, the method includes securing an expansion card via the application of a wedging force.

Abstract: A hot plug retainer and actuator is used on a chassis for releasably securing a component on the chassis. The retainer and actuator includes a one piece body having a first portion, a second portion and a living hinge pivotably connecting the first and second portions to one another for opening and closing the actuator.

Abstract: An electronic cartridge which may include an integrated circuit package that is mounted to a substrate. The substrate may include a plurality of conductive pads that are inserted into an electrical connector. The cartridge may be guided into the connector by a guide rail which has a latch slot. The electronic cartridge may include a latch which extends from a cover that is coupled to the substrate. The latch may extend into the latch slot to secure the cartridge to the connector.

Abstract: An apparatus for locking a printed circuit board inside a card cage is disclosed. For one embodiment of the locking assembly, the locking assembly is mounted on a printed circuit board. The locking assembly is movable from a unlocked position to a locked position to lock the printed circuit board into the card cage. The locking assembly is unmovable to return to the unlocked position without the aid of a separate unlocking mechanism.

Abstract: A faceplate assembly, for use with an electronic circuit card, comprising a faceplate and a movable plate, each including conductive portions or being made of a conductive material, and in electrical contact with each other. The faceplate is adapted to mount to an electronic circuit card, and has first and second opposite edges. The movable plate has a free edge and is movably coupled to the faceplate to move, by pivoting, sliding or the like, with respect to the faceplate between a retracted position and an extended position. Movement of the movable plate can be effected manually, or automatically by movement of the latches on the electronic circuit card assembly which latch the electronic circuit card assembly into an electronic circuit card housing.

Abstract: The card removal method and system easily removes a PCA card from a powered on computer system while minimizing damage to the computer system and to the individual removing the PCA. The printed circuit assembly card removal system is comprised of: an ejection card including at least a first ejector extending from the surface of the ejection card, the ejector having a first surface for pressing against the edge of the PCA card to be removed, and an ejection card holder for mechanically supporting the ejection card. To remove the PCA, the ejection card is pulled outward causing the ejector to apply a force to the edge of the PCA card to be removed, forcing the card edge fingers of the PCA card out of the PCA connector.

Abstract: An ejector for a printed circuit board overcomeably retains the ejector, e.g. in open and/or closed positions. Preferably a spring for providing a retaining force is integrally formed as part of the ejector body. When the ejector body is formed by injection molding, an injection gate is located to provide laminar flow of injection material through the spring area.

Abstract: The invention relates to an insertion/extraction tool for inserting and extracting printed circuit boards from a card cage. The invention uses fewer parts than the prior art and reduces bending stress on the printed circuit board by simultaneously applying the insertion or extraction force to both sides of the plane of the printed circuit board.

Abstract: An injector/ejector mechanism for a printed circuit card of the type that has front, rear and opposite side edges, a face plate at the front edge and a connector at the rear edge of the card in which slides on chassis card guides adjacent to the side edges of the cards to a home position in a chassis which connects that connector to a mating connector on a motherboard in the chassis. The mechanism includes a dog having spaced-apart first and second lobes, and a pivot pivotally connecting the dog to the card adjacent to the front edge thereof whereby the dog can pivot parallel to the card. The dog is pivotable between a first position wherein the first dog lobe overhangs the card side edge and engages a first surface of the card guide when the card is not in its home position and a second position wherein the second lobe overhangs the card side edge and engages a second surface of the card guide behind the first surface when the card is in its home position.

Abstract: A locking clip is disclosed for use with modular circuit packs that mount in mounting racks, and the insertion and extraction of circuit packs from a mounting rack is facilitated using a lever that is attached to the face plate of each circuit pack. When the novel locking clip is installed in a hole through the lever it is difficult to be seen and can only be removed with tweezers or similar small grasping tool. When in place the locking clip blocks the normal operation of the lever and the circuit pack cannot be removed from the mounting rack. Removal of the locking clip permits the lever to be operated normally to remove a circuit pack from the mounting rack.

Abstract: A computer system including a chassis and a microprocessor mounted in the chassis. An input device is coupled to provide input to the microprocessor and a mass storage device is coupled to the microprocessor. A display is coupled to the microprocessor by a video controller and a system memory coupled to provide storage to facilitate execution of computer programs by the microprocessor. A bezel is mounted on the chassis and a bezel door is pivotally mounted to the bezel. A latch is mounted to the bezel door. The latch is movable between a first position and a second position. A resilient member is operatively mounted between the bezel door and the latch. The resilient member is biased to maintain the latch in the first position.

Abstract: A chassis system for housing a plurality of circuit boards, such as PCI standard bus boards, provides a rack-mountable chassis having an open front side and a motherboard with a plurality of board connectors arranged side-by-side with respect to the front end. The boards are mounted in individual frameworks that facilitate ready installation and removal from the chassis. In particular, the chassis includes a plurality of receiving blocks at the bottom rear of the chassis, aligned with each of the motherboard connectors. The receiving blocks receive pivots mounted on the back of each framework. The framework is inserted into, and removed from the front opening of the chassis in an upwardly pivoted position that clears the motherboard connectors and other obstructions in the chassis. The framework is pivoted into and out of engagement with the motherboard when the pivot is located in the receiving blocks. The chassis can include top-mounted tracks. The tracks receive rollers on the framework.

Abstract: A computer in which an expansion card cage assembly is mounted in the computer chassis. The expansion card cage assembly includes a wall extending parallel to the chassis wall, a riser card mounted relative to the wall of the cage assembly and having a connector adapted to engage the connector of the motherboard, and at least one expansion card connected to the riser card. A lever is provided on the cage assembly wall and is adapted to engage the chassis wall to quick-detachably connect the cage assembly to the chassis.

Abstract: A processor support bracket is provided for mounting a processor cartridge package to a surface of a system baseboard of a personal computer. The processor support bracket includes a mounting section which is mounted to the baseboard to secure the cartridge package to the system baseboard. An end of the mounting section which is disposed adjacent to the surface of the baseboard has two spaced apart apertures which extend therethrough, transverse to the surface of the baseboard. Two slots are formed into the end of said mounting section and extend transverse to the apertures. The slots intersect the respective ones of the apertures and have widths for passing fasteners through the slots and into respective ones of the apertures for securing the mounting section to the system baseboard.

Abstract: A function extending apparatus for an information processing device including at least one first connector provided on a surface of the function extending apparatus for mounting the information processing device, and connected with at least one corresponding second connector provided on a lower surface of the information processing device, when the information processing device is mounted on the function extending apparatus. The function extending apparatus includes a pushing member moved in an upper direction so as to push the information processing device up from the function extending apparatus, a rotatable, and a push-up mechanism which moves the pushing member in the upper direction, when the operation member is rotated.

Abstract: A wireless communications device, such as a cellular telephone, is provided with a torsional hinging mechanism for rotatably coupling a flip cover to the device's main body. The torsional hinging mechanism both minimizes lateral loading and causes the flip cover to automatically assume the open position when released. One, and preferably two, torsional axles interconnect the main body to the flip cover. One end of the torsional axle is engaged by the main body so as to prevent relative rotation therebetween, for example by fitting the end through a retaining slit in the main body. The opposite end of the torsional axle is engaged by the flip cover so as to prevent relative rotation therebetween, for example by fitting a keyed end into a keyed hole. When the flip cover is in the closed position, the torsional axle is rotationally loaded so as to urge the flip cover towards the open position.

Abstract: The front system contains one lever pull handle (1) preferably both at the upper and the lower corner of the front element (38, 11). A latching slide (10) is mounted in each of these lever pull handles (1). Furthermore, a latching mechanism (22, 23, 26) is provided, which engages on the latching slide, as well as on a stressing mechanism (35) and on the front element (38, 11) such that the lever pull handle is held resting against the front element (38, 11) in a locked position. The latching mechanism can be unlocked again by a movement of the latching slide which is exerted on a pushing region (27) of the latching slide and is directed in a direction opposite to the pre-stress (52, 53) of the stressing mechanism.

Abstract: A method and implementing system are described in which planar board or motherboard stiffness is provided through a support structure mounted to the planar. The support structure includes support bars connected together to form a stiffening structure for the motherboard. The support bars are mounted within planes which are substantially perpendicular to the plane of the motherboard and in proximity to electrical connectors on the motherboard which are arranged to have circuit boards connected thereto. A board mounting apparatus is connected to the support structure to enable and guide the insertion and extraction of circuit boards to the motherboard with only enclosure side panel access. In one example, the circuit boards include guide pins which are inserted into slots of a mounting bracket, and the mounting bracket is selectively moved to exert an insertion or extraction force on a pin connector attached to the circuit board relative to a corresponding connector on a motherboard.

Abstract: A device for quickly guiding and positioning a main PC board in which the main PC board may be quickly and firmly installed (or removed from) on a computer housing, including one or more rotatable arrow-shaped push retaining blocks screwably secured on an end edge near an opening of the computer housing, and a corresponding number of slide rails provided at an underside of the main PC board such that the main PC board may slide along the slide rails into rail slots pre-formed in the computer housing and further into a predetermined position. Prior to positioning, a projecting block at one side of a front end of the slide rail is fitted into a notch at an inner side of the push retaining block, and the push retaining block is turned to allow the main PC board to be correctly pushed into the computer housing with contact ends at one side thereof engaging with a connector of an interface card.

Abstract: The present invention provides a shielded circuit board module comprising a conductive frame and conductive cover for substantially shielding an entire circuit board. Apertures are provided in the frame so that connectors on the circuit board are exposed through these apertures rather than shielded by the conductive frame. The assembled conductive frame, cover and circuit board form a shielded circuit board connector module. According to the invention the shielded circuit board connector module can be mated with another circuit board in a parallel configuration. A receptacle frame is preferably mounted on the other circuit board to permit the module to be easily inserted therein so that the circuit boards can be connected. The receptacle frame provides for easy extraction of the module from its connection with another circuit board.

Abstract: A heat transfer device for use with a retention assembly is herein disclosed. The retention assembly is mounted over one or more connectors attached to a circuit board. The retention assembly houses one or more processor modules that mount into the connectors. The processor modules include a heat transfer device. The heat transfer device has a pair of rail guides that cover the outer edges of the processor module. The rail guides enable the processor module to slide in and out of the retention assembly thereby enabling the processor module to be securely mounted into the connector.

Abstract: An apparatus for securing an add-in circuit card in an electronic device including a clamp movably coupled to the electronic device, the clamp configured to releasably engage the card upon movement of the clamp relative from a card engagement position in which the clamp is substantially inside the electronic device to a card disengagement position in which the clamp is substantially outside the electronic device. An apparatus for securing an add-in circuit card in an electronic device including a clamp movably coupled to the electronic device, the clamp configured to releasably engage the card upon movement of the clamp from a card engagement position to a card disengagement, and a switch for controlling electrical power to the card, the switch operated by the clamp such that movement of the clamp between the engagement and disengagement positions closes and opens the switch.

Abstract: An apparatus is provided for coupling a printed circuit board within a printed circuit board cage. The apparatus includes a baseplate and a latch. The baseplate is mounted to the printed circuit board. The latch is rotatably coupled to the baseplate. The latch includes a pivoting portion, a shaft, and a swell nut. The pivoting portion includes an ejector extending from an end of the pivoting portion. The ejector is engageable with the printed circuit board cage. The shaft is coupled to the pivoting portion. The swell nut is coupled to the shaft and engageable with the printed circuit board cage.

Abstract: A retention device for retaining the forward edge of a PCI or ISA adapter card in a computer frame is provided. The retention device has a channel mounted to the frame opposite a rearward edge of the card. The channel has upper and lower panels which define a slot for receiving the forward edge of the card. A finger is pivotally mounted to one end of the channel and has grooves on a lower surface for engaging grooves on an upper surface of the forward edge. The finger is movable between an engaged position for capturing the forward edge to retain it from moving, and a disengaged position for releasing the forward edge and allowing the card to be removed from the slot.

Abstract: This invention relates to a circuit board mounting apparatus with inverted U-shaped mounting arms for mounting a circuit board. The circuit board mounting apparatus comprises a base for loading the circuit board above it, two front end latching mechanisms installed on the base for removably and horizontally latching the front end of the circuit board, a supporting mechanism installed on the base for supporting the approximately center portion of the circuit board upward, and at least one inverted U-shaped mounting arm installed on the base having one open end facing downward. The open end of the mounting arm comprises an engaging means for engaging the rear end of the circuit board to prevent it from moving upward.

Abstract: An apparatus is provided for coupling a printed circuit board within a printed circuit board cage. The apparatus includes a baseplate and a latch. The baseplate is mounted to the printed circuit board. The latch is rotably coupled to the baseplate. The latch includes a pivoting portion, a shaft, and a swell nut. The pivoting portion includes an ejector extending from an end of the pivoting portion. The ejector is engageable with the printed circuit board cage. The shaft is coupled to the pivoting portion. The swell nut is coupled to the shaft and engageable with the printed circuit board cage.

Abstract: An apparatus is provided for coupling a printed circuit board within a printed circuit board cage. The apparatus includes a first portion coupled to the printed circuit board cage. A second portion is rotatably coupled to the printed circuit board, and includes a cam surface formed on a first end portion thereof. The cam surface is engageable with an interior surface of a bore in the first portion to urge the second portion and the printed circuit board from a first position to a second position. The second portion also includes a latch formed on a second end portion thereof. The latch is engageable with a corresponding latch on the printed circuit board in response to the second portion being located in the second position.

Abstract: A lever plate pivotally mounted on a bottom case of a main body of a computer including an extension, rotatable against a pack assembly to discharge same from a computer housing, and a deflectable detent lug selectively engageable with the pack assembly.

Abstract: The front system has an upper and a lower end piece (5) which are fastened to the upper and lower front corner region (3), respectively, of the printed circuit board assembly (3). An upper and/or a lower lever pull handle (19), which is fitted to the upper and/or lower end piece respectively, is used for levering the printed circuit board assembly into and out of the mounting rack. A latching mechanism (25) is provided to fix the lever pull handle in the appropriate position when the printed circuit board assembly has reached the point where it has been fully inserted into the mounting rack. A switching element (31) is integrated in the upper and/or lower end piece in such a manner that the switching element is actuated by the lever pull handle when it is in its fixed position. By this means, the printed circuit board assembly can be electrically enabled.