A peripheral computer enclosure includes a casing, a plurality of slots, a plurality of canisters being disposed in the slots, a plurality of storage devices, a plurality of canisters, a back plane, a power supply, a blower, a controller card and a personality board. The casing has an open front and a back. The slots are disposed inside the casing. The back plane is disposed in the casing. The power supply is disposed in the casing. The blower is disposed in the casing. Each storage device is disposed in one of the canisters. The back plane interconnects the storage devices. The personality board is connected to the back plane. The controller card is connected to the back plane.

This invention relates to enclosures for receiving and operating computer peripheral devices and more particularly to enclosures that allow computer peripheral devices, such as hard disk drives, to be readily interchanged and used in different combinations.
Computers include storage devices and other peripheral devices. These storage devices include compact disk drives, floppy disk drives, magnetic optical disk drives and tape back-up systems. These devices are connected by wires and are operated in conjunction with a computer. The spectacular proliferation of electronic devices, particularly computers, in modern society, both in numbers and complexity, demands that such devices satisfy ever-increasing standards of reliability and serviceability to avoid degeneration into chaos. In the early days of the computer industry, relatively high failure rates and corresponding "down time" when the computer system was unavailable to perform useful work were accepted as the norm. As the industry has matured, computers have become more reliable, and users have come to depend on these systems being available when needed. This dependence has become so profound that, for many businesses, the mere unavailability of the computer system for any appreciable length of time can cause significant commercial injury.
In the early days of the computer industry, a computer component was replaced by shutting off power to the system, replacing the component, and re-powering the system. This is a logical way to fix a toaster, but the complexity of modern computers makes this undesirable. It is not possible to simply shut off power and then turn it back on as one would a light bulb. A computer system's state and data must be saved when it is powered down. Its software must be reloaded, and its state restored, when it is re-powered. For a large modern computer system, these operations can take a very significant amount of time, during which the system is unavailable to its customers.
Computer manufacturers are well aware of the dependence of their customers and have accordingly devoted considerable attention to these problems. As a result, many modern computer systems have some degree of fault tolerance and are capable of concurrent maintenance. Fault tolerance means simply that a single component of the computer system may fail without bringing the entire system down, although in some cases performance of the system or some other characteristic may be adversely affected. Concurrent maintenance is the capability to repair or replace some component of a computer system without shutting down the entire system. The system can continue to operate and perform useful work (although possibly in a diminished capacity) while the repair is being performed. When a computer system is both fault-tolerant and capable of concurrent maintenance it can, in theory, be kept running 24 hours a day for an indefinite length of time. In fact few, if any, computer systems achieve this level of reliability with respect to every component which may possibly fail.
One example of this type of fault tolerance is an array of storage devices known as a redundant array of independent disks. A RAID system stores data on multiple storage devices in a redundant fashion, such that any data can be recovered in the event of failure of any single storage device in the array. RAID systems are usually constructed with rotating magnetic hard disk drive storage devices, but may be constructed with other storage devices such as optical drives, fiber channel devices and tape drives. A paper entitled, "A Case for Redundant Arrays of Inexpensive Disks", by Patterson, Gibson & Katz and presented at the ACM SIGMOD conference (June, 1988) describes RAID systems that provide different levels of redundancy or other operating characteristics and classifies five types of RAID, designated levels 1 through 5.The Patterson Nomenclature has become standard in the industry. RAID systems have proliferated to the point where an industry trade group called the RAID Advisory Board has attempted to establish standards for RAID characteristics. Further information regarding RAID systems can be found in The RAID-book, A Source Book for Disk Array Technology, published by the RAID Advisory Board (5th Ed. February 1996).
Frequently, a RAID system is manufactured and marketed as a stand-alone storage system that is housed in its own cabinet with its own power supply and supporting hardware and software and that communicates through a standard communications interface with a host computer system. Since it is desirable to make data available to the host system at all times, even if a single storage device in the RAID system fails, the RAID system will frequently have its own on-board data recovery capability that may include temporary spare drives for storage of recovered data. The RAID system may have redundant power supplies or other redundant components.
Electronic systems frequently use back-plane circuit cards for distribution of power, data signals and/or mounting of active or passive circuit elements and connectors. Such a card typically contains multiple parallel layers for embedded circuit patterns, grounds, or power distribution. Pluggable connectors couple the back-plane to other modules which make up the electronic system, such as power supply modules, storage devices, or logic cards. A back-plane card acts primarily as a distribution medium. The back-plane card conveys power and/or data signals from one module to another and contains relatively few functional components attached directly to the back-plane itself. The back-plane contains functional components.
A back plane contains embedded power planes for distributing electrical power to pluggable modules or other attached devices. It also contains a multiple ground planes. One of the power planes is associated with ground and must be grounded. Grounding insures that electrical paths of negligible resistance are created between ground planes and the zero volts power plane.
The existence of such paths causes parasitic current to flow in the ground planes and lowers the noise immunity of the system. It is desirable to reduce the parasitic current flowing in the ground planes of a back-plane circuit card, particularly a back plane that distributes power to multiple pluggable modules.
U.S. Pat. No. 4,977,532 teaches a computer that includes computer cards, disk drives and power supply circuitry that are mounted in a drawer assembly that is readily removable from the rear of the cabinet.
U.S. Pat. No. 6,025,989 teaches a rack mounted multiprocessor in a computer that has a node assembly. The node assembly has a logic chassis and a removable chassis. The logic chassis contains logic cards that include memory cards, a service processor card, central processing unit processor cards and input/output cards to which input/output and processor interconnecting cables are attached. The removable chassis contains the power supply module for the node, a node supervisor card, disk drives and cooling fans. The removable chassis is removable from the logic chassis without moving or disturbing the logic chassis. One fan of a pair of cooling fans in the removable chassis draws air through the power supply that has relatively higher cooling needs and blows the air into the logic chassis over logic modules that have relatively lower cooling needs. The other cooling fan draws air over the disk drives and node supervisor card and blows air over into the logic chassis over logic modules that have relatively higher cooling needs.
U.S. Pat. No. 5,604,873 teaches a disk drive controller that has a plurality of disk drive interfaces. Each disk drive interface includes a connector and a delay circuit. A set of power application circuits has a server which supports hot docking of SCA drives. Each connector mates with a hot docking disk drive having equal length connecting pins and detects the presence of such disk drive when the hot docking disk drive makes contact with the connector. Each delay circuit generates a set of properly delayed enabling signals to the corresponding power application circuits. Each set of power application circuits regulates power applications to the hot docking disk drive making contact with the corresponding connector. The delayed and regulated manner of applying power prevents voltage and power swings that might disrupt on-going operations and/or cause damages to the neighboring drives.
U.S. Pat. No. 5,790,374 teaches a computer cabinet and hot-pluggable disk drive module design that includes an indicator light support for the disk drive module. The cabinet includes a disk drive module-receiving bay into which the disk drive module is removably installed. The disk drive receiving module bay includes a back plane having at least one connector for engagement with a corresponding connector that is a single connector architecture connector, protruding from a leading surface of the disk drive module. A light source mounted to the back plane near the back plane connector is illuminated to provide status information concerning the disk drive module. A light conduit extends from the light source to a conspicuous viewing location on the computer cabinet. Multiple indicator lights and corresponding light conduits are tinted to different colors and may be employed to provide different status indications, such as power, activity and fault status information. The light conduits are incorporated into the disk drive modules. Once the disk drive module has been installed within the drive bay the light conduits extend from a location on a leading surface of disk drive tray opposing the light sources contained on the back plane to a conspicuous viewing location on a visible surface of the disk drive module.
U.S. Pat. No. 5,862,313 teaches a system that implements a serial RAID system. Data is striped for an array of disk drives and parity for the striped data is calculated and the resulting data and is written serially to a RAID system over a Fiber Channel or other type of network. The system also allows reading of the striped data and parity serially from the disk array.
U.S. Pat. No. 5,812,754 teaches a modular and highly available RAID system that has a fiber channel arbitrated loop interface coupled with a disk array. Fault-tolerant operation is assured. The system provides dual and isolated arbitrated host and storage device loop circuits for redundant, independent input/output paths to local and/or remote host computers. Each loop includes bypass circuits. The bypass circuits prevent the failure of any device (host computer or storage device) from affecting the operation of loop. Orthogonal data striping may be used to further assure data integrity.
U.S. Pat. No. 5,805,788 teaches a system that implements RAID-5 parity generation and reconstruction. Data for an array of disk drives is placed in an input/output buffer. The RAID-5 parity engine creates parity data and stores the resulting parity data in the input/output buffer as well. The input/output buffer (both the data and the parity) is then sector-striped across a network of disk drives, such as a Fiber Channel network. The RAID-5 parity engine creates parity on multiple stripes of data upon a single activation of the engine. The RAID-5 parity engine can reconstruct a sector of data using the parity information. The RAID-5 parity engine can also check the data against its expected parity.
U.S. Pat. No. 5,740,397 teaches an adapter for use in a computer system. The adapter has an IDE interface controller and a plurality of drives. The adapter is connected to the IDE controller and the plurality of drives and monitors information transmitted between the IDE interface controller and the plurality of drives. The adapter determines whether each of the plurality of drives is serviceable and whether data on each of the plurality of drives are equal. Identical data is directed to each of the plurality of drives when data on each of the plurality of drives are equal. Data is prevented from being directed to at least one of the plurality of drives when data on each of the plurality of drives are not equal. One of the pluralities of drives is selected as a drive from which to read data.
U.S. Pat. No. 5,515,515 teaches a small computer system interface disk array subsystem that has removable disk drive units that can be removed while the subsystem has power applied to it and is operational. In order to prevent malfunctions of other disks in the disk array, and in order to prevent rapid fluctuations in the current in the power circuits of the subsystem, the power and the data and control signals are applied to the inserted disk drive unit in a phased sequence. The ground of the disk drive unit is connected to the ground of the subsystem. A pre-charge power connects the power buses of the disk drive unit to the power buses of the subsystem through resistors so that capacitance is connected to the power buses of the disk drive unit is charged gradually through the resistors rather than abruptly. Power is applied directly from the power buses of the subsystem to the power buses of the disk drive unit. Finally, the control and data signal connections are made between the subsystem and the disk drive unit. This phased sequence of connections between the subsystem and the disk drive unit is accomplished by providing sets of contacts having differing lengths in a connector on the disk drive unit so that some connections are made before other connections.
U.S. Pat. No. 5,438,226 teaches an enclosure for heat-generating electronic components that establishes an airflow path for cooling air. Powered air movers force air through the enclosure. One powered air mover is mounted at the air inlet to the enclosure, and the other of which is mounted at the outlet. Only one air mover is used at a time. In the event of failure of the air mover being used, the remaining air mover begins operation. The total cooling airflow passes through both air movers. The air movers may be arranged in series with respect to the airflow. Because the air movers are mounted in series with respect to the airflow, the airflow pattern is substantially the same regardless of which air mover is currently operating. Hot spots may result when one fan in a fan bank fails. The enclosure may house a redundant array of independent disks of a computer system. The air movers are arranged serially with the airflow and may be used to provide additional cooling for severe operating conditions.
U.S. Pat. No. 5,991,852 teaches a memory system that includes a main memory such as a cache memory and a shadow or back-up cache memory in conjunction with a write cache. The shadow memory is coupled to the same data bus as the main memory and is written to simultaneously. There is no latency between writing to the main memory and writing to the shadow memory. Redundancy is provided for by having a switching circuit that allows control of the shadow memory to be transferred to a second controller upon failure of a first controller. A unique layout arrangement for a RAID chassis is also described in which back-to-back circuit boards are mounted in the center of the chassis and a main bus on one board becomes the shadow bus on the other board, providing a mirror arrangement for the circuit boards.
U.S. Pat. No. 6,058,019 teaches an electronic system that contains a back-plane circuit card assembly for distribution of electrical signals among component devices. Power is distributed in embedded power planes. One plane is associated with ground. The back plane also contains multiple embedded ground planes. The circuit card assembly is divided by an axis into two halves, each half receiving and consuming approximately equal power. Electrical couplings for power sources and power planes in each half of the back plane are located symmetrically with respect to the axis. A row of ground vias along the axis couples the ground planes to the associated power plane. At all other locations on the back plane the ground planes are electrically isolated from the associated power plane. The back-plane assembly includes a pair of base cards, connected by a single smaller jumper card in which all ground vias are located. Each base card lies on a respective side of the axis, the jumper straddling the axis. An intelligent redundant array of independent disks storage server has concurrent maintenance capability.
U.S. Pat. No. 5,822,184 teaches a modular data device assembly for a computer that has a housing that is designed to fit into a conventional, industry standard size expansion bay. Individual plug-in data storage devices, such as hard disk drive and compact disk drives, are disposed vertically in a stacked formation within the housing. A motherboard with plug-in connectors to which the drives are connected allows easy replacement of defective data devices, which devices slide in or out. The disk drives and modular data device assemblies may be arrayed in either series or in parallel to a controller. By its modular structure and redundant storage functions, the device benefits from what is known as the principle of an redundant array of inexpensive disks.
U.S. Pat. No. 5,797,667 teaches a hard disk drive mount. The hard disk drive mount includes a stop bar at either side of a front end of a hard disk drive frame. The stop bars prevent a pull handle on a case of the hard disk drive frame from being forcefully pulled up thereby protecting the hard disk drive lock. The relative movement between the pull handle and the stop bar results in a counter force between the case and a mount to cause two connecting ports to be separated to permit smooth removal of the hard disk drive.
U.S. Pat. No. 5,828,548 teaches a removable hard disk drive mount that includes structures at the end of a rack. The structures of the disk drive mount cooperate with structures on the shaft of a pivotal handle to ensure that final insertion of the hard disk drive casing into the rack is carried out in an even manner without excessive force. The mount includes two notches. The two notches are disposed at the end of a pivotal shaft of a handle for the casing. Corresponding angles and bent portions of the rack permit final insertion of the hard disk drive casing into the rack only when the handle is turned from a horizontal to a vertical position.
U.S. Pat. No. 5,886,869 teaches a sleeve that holds a hard disk drive in portable removable engagement with a computer. The sleeve includes a base and a cover attachable to the base by mechanism of threaded fasteners. The base includes plural holder arms. When the cover is removed from the base and the hard disk drive advanced into the base, the holder arms move outwardly as the hard drive rides on the arms. When the hard disk drive clears the arms, the arms, which are biased to a hold configuration, move back inwardly to hold the hard disk drive in the base, with the cover then attached to the base. The edge of the cover cooperates with the base to hold the holder arms in the hold configuration and thereby securely hold the hard disk drive in the sleeve.
U.S. Pat. No. 5,741,055 teaches a hard disk drive converting drawer that includes a drawer and a fixing seat. A pull handle is back and forth slidably disposed at the front end of bottom side of the drawer. A transverse beam is disposed between two balance levers of the pull handle for back and forth pulling an auxiliary lever to press and close/open a touch switch. When the touch switch is pressed and closed, the auxiliary lever is forced by a leaf spring disposed on one side to retract the pull handle to a hidden position. When the touch switch is bounded open, the pull handle is pushed and ejected for a user to easily pull out the pull handle. When pulling the pull handle, the auxiliary lever is driven to push a stopper block projecting from one side of the fixing seat so as to smoothly draw out the drawer from the fixing seat for taking out the hard disk drive.
U.S. Pat. No. 5,808,871 teaches a modular tower that has a plurality of bays. The bays are fitted with rails upon which individual trays are able to slide. The trays are detailed to carry electronic components. Each tray is fitted with electrical connectors that are connected to corresponding electrical connectors on a back plane in the tower. The tower can be employed vertically and horizontally. The tower has easily removable top and side panels. A base may be adjustably secured to one or more of the towers. The front thereof is fitted with a removable frame that carries a hinged door. The frame can be removed and rotated 180 degrees in order to change the swing of the door from left to right and vice-versa.
U.S. Pat. No. 5,788,347 teaches a system that interlocks computer peripheral enclosures.
U.S. Pat. No. 5,067,041 teaches a shielding strip for a computer that includes an electrically conductive housing and a non-conductive drive mounting structure situated within the housing.
U.S. Pat. No. 5,224,019 teaches a modular computer chassis that includes a main chassis. A motherboard is attached to the main chassis and a sub-chassis that is attachable to the main chassis. The sub-chassis has at least one computer component that is attached thereto such that the computer component is electrically connected to the motherboard. The computer component is separable from the main chassis by removing the sub-chassis from the main chassis. The sub-chassis contains those computer components subject to mechanical wear and most often requiring replacement, such as the power supply and hard disk drives. The sub-chassis is mechanically connected to the main chassis by using slots and tabs such that when the cover is in place upon the computer, then the sub-chassis is secured therein. The sub-chassis and the computer components disposed thereon thus form a module which is conveniently removable and replaceable such that those computer components most frequently requiring service is quickly removed and replaced by a person unskilled in computer repair.
U.S. Pat. No. 5,420,750 teaches computer apparatus that includes a compartment and a plurality of modules. Each module has a disk drive memory package and is inserted in a compartment.
U.S. Pat. No. 4,754,397 teaches a fault tolerant computing facility that includes a housing array for containing a plurality of hardware element modules such as disk drives, a plurality of modularized power supplies and plural power distribution modules.
U.S. Pat. No. 5,227,954 teaches a mounting arrangement which allows drives of different sizes to be mounted in a drive dock and the hardware device necessary to mount full height, half height or third height drives in a conventional size drive dock. The hardware device provides mounting plates which have upper and lower ridges for mounting a single disk drive of varying size within the single drive dock.
U.S. Pat. No. 5,222,897 teaches a circuit board inserter/ejector system which is for inserting a circuit board into a back plane in a chassis and for ejecting the circuit board from the back plane of the chassis. The inserter/ejector system can be used with a magnetic disk drive to facilitate insertion and removal thereof within a computer.
U.S. Pat. No. 5,224,020 teaches a modular electrical apparatus that includes a plurality of customer removable electrical devices such as disk drives. The devices and support units are all blind pluggable into a removable central electrical distribution unit.
U.S. Pat. No. 5,006,959 teaches a computer apparatus with modular components including segregated functional units like a disk array, various plug-in card packages, a plurality of power supplies, a plurality of fan units and a motherboard. Another goal for moving towards modular computer components is to improve reliability. A number of disk drives are interconnected in an array for redundant storage of data. Failure of one disk drive does not destroy irreplaceable data.
U.S. Pat. No. 5,119,497 teaches a computer that has modular components and is used/replaced on a common base mount. The computer also has a motherboard with some number N of connect-receptacles thereon. A deck is superposed to form a plenum above the motherboard and is characterized by N like aperture sets, a connector-slot in registry with each connect-receptacle and several like removable, circuit-modules. An air cool arrangement is arranged to draw cooling-air into the circuit-modules and down upon and across the motherboard.
U.S. Pat. No. 5,844,776 teaches a static memory device that has compatibility with a disk drive installed in an electronic apparatus as an external storage unit. The static memory device has a first memory board arranged on the same base portion as the one on which the disk drive can be installed, the first memory board having the same projected area as the disk drive.
U.S. Pat. No. 5,852,546 teaches a computer includes a chassis and a hard disk drive. The hard disk drive is mounted in the chassis of the computer.
U.S. Pat. No. 5,602,696 teaches a computer system that provides for quick removal and quick and simple installation of a disk drive into the system.
U.S. Pat. No. 5,327,308, U.S. Pat. No. 5,122,914, U.S. Pat. No. 5,515,215, U.S. Pat. No. 5,517,373 and U.S. Pat. No. 5,563,748 teach a computer system that provides for quick removal and quick and simple installation of a disk drive unit into the system.
U.S. Pat. No. 5,119,270 teaches a multimedia data storage system that includes a compartmentalized drawer which can be tailored to accommodate the differing cooling requirements of different device types thus allowing each device type to be mounted in any device position.
U.S. Pat. No. 5,207,613 teaches a high-density electronic module packaging system that includes a cabinet for housing a plurality of modules. Disposed at the rear of the cabinet and forming a rear wall thereof is a cooling system that is used for cooling the modules that are contained in the cabinet. Disposed within the cabinet are four cooling modules, a power distribution unit having twelve power converters and twenty-eight electronic modules. The number of cooling modules, power converters and electronic modules may be added or subtracted as needed or desired. The cooling modules allow the flow of cooling fluid to and/or from the power distribution unit and/or to the plurality of electronic modules. The power distribution unit supplies power to the plurality of electronic modules. The electronic modules may house one or more sub-modules such as storage disk drives or printed circuit boards.
U.S. Pat. No. 5,379,184 teaches a multi-module storage array that includes cabinets. Each cabinet has a number of identical bays.
U.S. Reissue Pat. No. 34,369 teaches an adapter that is provided for a removable information storage device in an information storage and retrieval system or control system.
U.S. Pat. No. 5,471,099 teaches a modular enclosure apparatus for a personal computer and a workstation that has a plurality of removable and replaceable modules. These modules include a cooling module for cooling the enclosure. A memory storage device module has a plurality of mating slides and carriers for routine installation and removal of each memory storage device and a power supply module for providing power to the enclosure. The modular enclosure apparatus includes a RAID controller module that is similarly removable and replaceable. Each module may include a circuit interrupt assembly for disabling individual modules by cutting off power to the desired module and allowing that module or parts contained therein to be removed while the power is disabled only to the module desired and the remaining modules continue to be enabled.
U.S. Pat. No. 5,247,427 teaches a disk array system that is for use in a data processing system. The disk array system includes a chassis having a top wall, a bottom wall, two side-walls, an open front end and an open rear end. Disposed within the chassis are three power supplies, a pair of controller boards, a back plane and a set of twenty disk drive modules.
U.S. Pat. No. 5,604,662 teaches an expandable modular data storage system that includes a plurality of data storage devices and a plurality of identical, vertically stackable storage device housings. The housings slidably receive a data storage device and mechanical connection elements for releasably connecting the top of one storage device housing to the bottom of a storage-device housing stacked thereon.
U.S. Pat. No. 6,061,250 teaches a full enclosure chassis system with tool-free access to hot-pluggable circuit boards therein. The system includes a front access plate that can be opened and closed from the front of a primary chassis when mounted within a secondary chassis so that only the front access panel is externally accessible. When the front access plate is in an open position, circuit boards within the full enclosure chassis system can be hot-pluggably removed and inserted without powering down the system or disrupting any component of the system. The full enclosure chassis system supplies standard connector access to the components that are external to the system and are connected by standard connectors disposed at the back plane at the back panel of the system.
U.S. Pat. No. 5,777,845 teaches a disk array which includes a mainframe chassis conforming to standard SCSI disk drive mechanical form factors, and a motherboard and a RAID controller within the chassis. The motherboard interconnects electrical signals between the electronic modules, at least some of which include disk drives forming a redundant array of independent, or inexpensive, disks. One of the electronic modules is a secondary power supply module that is connectable to the motherboard. The RAID controller is electrically connected to a system host power supply and a host interface bus. Through the RAID controller the motherboard interconnects all the electrical signals between the system host power supply and the host interface bus with the secondary power supply module and the RAID disk drives.
U.S. Pat. No. 6,065,096 teaches a RAID controller which is integrated into a single chip. The RAID controller chip includes a general purpose RISC processor, memory interface logic, a host central processing unit peripheral component-interconnect bus, at least one back-end input/output interface channel, at least one direct memory access channel, and a RAID parity assist circuit. The RAID chip enables higher integration of RAID functions within a printed circuit board and in particular enables RAID function integration directly on a personal computer or workstation motherboard. The back-end input/output interface channel is a dual SCSI channel. The RAID chip is operable in either of two modes. In a first mode, the chip provides pass through from the host central processing unit interface directly to the dual SCSI channels. This first mode of operation, a SCSI pass-through mode, allows use of the chip for non-RAID storage applications and enables low level manipulation of the disk array in RAID applications of the chip. The first mode of operation permits use of the chip without change to host applications and drivers. Rather, the chip is operable in a manner compatible with known available SCSI controller devices. The second mode of operation, a RAID control mode, provides full RAID management features to the attached host central processing unit. The RAID chip presents an intelligent input/output interface to the host central processing unit to enhance portability and performance of the host/RAID interaction.
U.S. Pat. No. 6,061,752 teaches a technique that allows hot plugging a peripheral controller card, containing both a local bus and a peripheral bus on a single connector, into a host system board containing a host system bus and a host input/output bus. When mating the peripheral controller card to the host system board a local device power supply is inactive, a peripheral device power bus is powered, and signal lines of a peripheral device are maintained in a high impedance state. Following a delay after the mating, the LDPS is activated by the host operating system. Following the activation of the LDPS, the host system bus is coupled to the single connector through switches that are under OS control. In response to the activation of the LDPS, the signal lines of the peripheral device are enabled. The peripheral controller card is a disk array controller card, the local bus is a peripheral component-interconnect bus and the peripheral bus is a SCSI bus. The disk array controller card is coupled to a mass storage peripheral and is programmed for RAID. A peripheral component-interconnect bus and a SCSI bus are carried on a single peripheral connector in order to provide cable management and readily allow hot plugging a redundant peripheral controller card into the host system board.
U.S. Pat. No. 6,058,054 teaches a system that provides a backup of a portion of a source drive of a plurality of drives in a redundant array of inexpensive disks data storage system. The portion of the source includes a plurality of segments. The system includes a source drive that is associated with a target drive of the plurality of drives.
U.S. Pat. No. 6,018,456 teaches an enclosure system that receives a number of plug in computer peripheral devices that includes hard disk drives in a disk array and utilizes front and rear cages or enclosures that are separated by a vertical back-plane. The back-plane has internal circuit interconnections and multi-pin docking connectors on each face. The system enclosure for receiving a number of computer peripheral devices to be plugged into and removed from interconnecting circuits includes front and rear cage enclosures. Each cage has a rectangular outline and open front and rear sides relative to an insertion axis the front cage enclosure including guide mechanisms that may be positioned at different elevations on the sides thereof to accommodate combinations of peripheral devices of different heights. A back plane circuit board has front and rear faces and being mounted vertically between the rear of the front enclosure and the front of the rear enclosure. The back plane circuit board includes multi-pin docking circuit connectors on the front and rear faces. Each of a plurality of computer peripheral holding units may be inserted through the front of the front cage enclosure into engagement with connectors on the front face of the back plane. Each of a plurality of support modules may be inserted through the rear opening of the rear enclosure into engagement with the connectors on the rear face of the back plane.
With the advent of disk arrays a number of hard disk drives are used together with a data processing system in order to provide high storage capacity. Manufacturers early adopted the approach of mounting a number of disk drives in a single enclosure. This became possible after hard disk drives and other peripherals became available that were compact, in successively smaller formats (8 inch, then 5¼ inch, then 3½ inch) while achieving high capacity storage now in the gigabyte range. Host computers and disk drive controller cards were designed to operate different disk drives in interrelated fashion on data to be stored by employing disk striping to distribute a data block among a number of disk drives. Data distribution was used to substantially increase data transfer rates, and also to facilitate error correction, using redundancy to improve reliability. These developments also led to the introduction of a number of variants that became referred to as RAID technology, which now encompasses tape drives as well as hard disk drives. Among the features adopted were the use of exchanges of spare drives for defective drives, and the mounting of disk drives and other peripherals in plug-in cassettes, canisters or trays of different configurations. These allowed the peripherals to be inserted into and retained in the enclosure and enabled completion of electrical power and data transfer connections. The peripheral devices could be removed in a "hot swapping" approach that precluded the need for shutdown. There are now many different types of enclosures for removable computer peripheral devices that include hard disk drives in RAID and non-RAID arrays. A number of adapter systems are available that are employable with a standard computer port or receptacle (now typically 5¼ inches or 3½ inches) to enable a smaller sized peripheral within a cassette or canister to be removably inserted. These systems include local controller cards, personality cards, power supplies and interconnects for the different computer peripheral devices. As the array systems and structures have become available in larger volume, system requirements have come into conflict with demands for greater versatility in use along with customer insistence on reduced cost. Current demands are for enclosures that can incorporate different sizes of disk drives, so as to accommodate different storage capacities or different device preferences. In 3½ inch drives higher capacity units are taller (1⅝ inches) than lower capacity (1 inch high) units even though both fit within a port or bay designed for a 3½ inch drive. An enclosure accommodates an integral number of whatever height drive is to be used or even allow a mix to be employed. Another respect in which the enclosure is adaptable relates to the different types of bus interconnections that may have to be made. The host input/output connection can be any of a number of different types. The local bus peripheral bus interconnections can also be of one of many different types, such as SCSI, IDE, and peripheral computer interconnect devices. There is also growing adoption of a connection approach known as Single Connector Attachment. It is therefore desirable to have available an arrangement in which only a back plane need be interchanged if different buses are to be used. The multiple pin mating connectors and cables used with different buses also should be readily changeable for different configurations. When configurations change, the user interface (display and controls) should likewise be changed to be compatible.
U.S. Pat. No. 6,331,933 teaches a power sub-frame that has four walls defining first, second, third and fourth sides of a open, rectangular frame. A fifth side is open for receiving a plurality of power supply units for powering the system unit. A power distribution board located at a sixth side of the frame opposite to the open side, for making electrical contact to the power supply units. The power sub-frame can be manufactured as a sub-assembly for a system unit, facilitating manufacture, testing and maintenance. The power sub-frame can be pre-assembled with power distribution logic and cabling ready to be mounted in a system unit. The system unit can, for example, be a computer system unit for rack mounting in a telecommunications application.
U.S. Pat. No. 6,201,692 teaches a disk drive enclosure that houses a mix of "slim" and "half high" disk drive sizes in almost any order. The disk drive enclosure includes at least thirteen equally spaced pairs of guide rails.
U.S. Pat. No. 6,313,983 teaches a computer enclosure that includes and an inner casing and an outer casing that receive the inner casing therein. The inner casing includes a bottom panel and a front panel that extends upright from the bottom panel. A disk drive rack is arranged above the bottom panel and attached to the front panel. A main board support panel supporting a main board is attached to the front panel, the bottom and the disk drive rack on a first side of the inner casing. A support member is connected between the disk drive rack and the bottom panel on an opposite second side of the inner casing for enhancing mechanical stability of the structure of the inner casing. The support member has an upper end pivotally attached to the disk drive rack. The support member is movable between an open position where the support member is substantially located outside the inner casing for facilitating maintenance and a closed position where an lower end of the support member engages with the bottom panel to releasably secure the support member to the bottom panel. The support member defines three sets of openings for selectively and interchangeably engaging with pawls of three receptacles containing power supplies of different specifications. Power supplies of different specifications may be selectively mounted to the computer enclosure.
U.S. Pat. No. 6,272,573 teaches a storage system for a computer system in which the storage capacity can be incrementally increased without disrupting the operations of the storage system. The storage system includes a base unit and a plurality of modular units. The modular units are inserted into the base unit when increased storage capacity is required. Each modular unit has an enclosure including a top wall, a bottom wall and two side walls. The bottom and top walls each have at least one power connector and data transmission connector. The bottom wall of a first modular unit attaches to the base unit and the top wall of the first modular unit can attach to the bottom wall of a second modular unit. At least one back plane is provided in each modular unit for providing attachment for a set of storage devices. A data transmission interconnect system transmits data and commands between the plurality of storage devices in the modular units and an external source. In the event of a loss of connection to any one set of storage devices data and commands can still be transmitted from and to any other set of storage devices. Application programs running on a host system issue requests to access data stored on the storage devices that are routed through an input/output bus adapter. An input/output bus itself is the medium in which host commands, disk responses and data are moved between adapters and the storage devices. A disk controller connects a host computer's input/output bus to the storage device input/output bus through a bus adapter channel. The input/output buses are small computer storage interconnect devices to the serial storage architecture and the fiber channel arbitrated loop. Storage subsystems also include power converters. Power from commercial AC power sources needs to be converted to DC power and further converted to supply the amount of power needed for the hard disk drives and the cooling fans in the subsystem. Redundancy is required in all aspects of the storage system, including the hard disk drives, the cooling fans and the power converter systems.
U.S. Pat. No. 6,118,776 teaches an apparatus that provides a fiber channel interconnection between a plurality of private loop devices through a Fiber Channel private loop device interconnect system. The Fiber Channel private loop device is connected to two or more Arbitrated Loops containing one or more private loop devices. The interconnect system includes a routing filter to filter incoming arbitrated loop physical addresses to determine which fiber channel frames must attempt to be routed through the fabric. Numerous topologies of interconnect systems may be achieved.
U.S. Pat. No. 6,338,110 teaches a data storage system that includes a first storage channel, a first controller that is coupled to the first storage channel and a first storage device that is coupled to the first storage channel. The system also includes a second storage channel, a second storage device that is coupled to the second storage channel and a switch that is coupled to the first storage channel and the second storage channel. The switch separates the first storage channel from the second storage channel in a first state and connects the first storage channel and the second storage channel in a second state. For disk drives and RAM disks, a storage array is commonly called a disk array, in which a disk controller connects a host computer to multiple disk drives. The disk controller provides access to the actual drives in a just a bunch of drives configuration or performs striping of data across the drives in a redundant array of independent disks configuration. Storage channels include an AT Attachment, a small computer system interface, a fiber channel or storage system architecture. The external access interfaces often include industry standard architecture, bus or peripheral component-interconnect bus for host adapters, SCSI, fiber channel, or SSA. For tape drives, the storage array commonly includes individual tapes or tape silos. The controller may provide data striping capability across the tapes. The storage channels and external access interfaces are usually the same as for disk drives. For memory chip storage devices, the storage array commonly is the main processor memory, cache memory, or other memory subsystem. The controller commonly performs error detection and correction (parity and ECC) and provides data striping (usually called interleaving). The storage channels are the memory buses. The external access interfaces are commonly peripheral component-interconnect bus or processor bus. In order to maintain access to the storage devices in the event of a single controller failure (to provide high-availability), two controller cards may be attached to the same storage devices, in a dual-controller configuration. One controller may provide access to one set of storage devices and the other controller may provide access to another set of storage devices.
U.S. Pat. No. 6,304,942 teaches a system that upgrades an original data storage system into an enhanced data storage system. The data storage system includes a storage array controller device and a storage array. The data storage system is initially connected to a host system via a host bus and presents to the host system an original logical volume mapping associated with a logical identifier and mapped to a physical data set stored in individual storage devices in the storage array. An enhanced storage array controller device is operatively connected to the host system via the host bus and the storage array controller device and a storage connection device coupled to another storage array are operatively connecting to the enhanced storage array controller device via an intermediate bus. The physical data set of the storage array is redistributed across a plurality of storage arrays, including the original and the other storage arrays. The enhanced storage array controller device is reconfigured to present to the host system a logical volume mapping associated with the logical identifier mapping to the physical data set redistributed across the plurality of storage arrays. Other storage controller cards do not provide RAID functionality and merely present the host system with access to multiple disks in an enclosed array (often referred to as a JBOD) without providing the virtual disk functionality. When a JBOD is connected via a SCSI bus, for example, each disk is addressed with both a SCSI Target ID and at least one LUN. Such storage controller cards do not provide RAID functionality, but are intended primarily to provide access to multiple disks and to monitor the environment within a disk array enclosure.
U.S. Pat. No. 6,243,787 teaches an apparatus that conveys data over a packet-switching network. Data are received from a peripheral device for transmission via the network to a memory associated with a central processing unit, followed by an interrupt signal from the peripheral device associated with the data. One or more data packets containing the data are sent over the network to a host network interface serving the memory and the central processing unit, followed by an interrupt packet sent over the network to the host network interface. Responsive to the interrupt packet, an interrupt input of the central processing unit is asserted only after the one or more data packets have arrived at the host network interface. In current-generation computers, the central processing unit is connected to the system memory and to peripheral devices by a parallel bus, such as the ubiquitous Peripheral Component Interface bus. As data path-widths grow, and clock speeds become faster, however, the parallel bus is becoming too costly and complex to keep up with system demands. In response, the computer industry is moving toward fast, packetized, serial input/output bus architectures, in which computing hosts and peripheral are linked by a switching network, commonly referred to as a switching fabric. A number of architectures of this type have been proposed, including "Next Generation input/output" and "Future input/output," culminating in the "INFINIBAND" architecture, which has been advanced by a consortium led by a group of industry leaders (including Intel, Sun, Hewlett Packard, IBM, Compaq, Dell and Microsoft). Storage Area Networks provide a similar, packetized, serial approach to high-speed storage access, which can also be implemented using an INFINIBAND fabric. In a parallel bus-based computer system, when a peripheral device needs to deliver data to the central processing unit, it typically writes the data to the memory over the bus, using direct memory access. When the peripheral has finished writing, it asserts an interrupt to the central processing unit on one of the interrupt lines of the bus. Bus arbitration ensures that the central processing unit will not attempt to read the data from the memory until the writing of the data is complete. When a packet-switching fabric connects a peripheral device and a central processing unit they operate asynchronously. The data sent to the memory and the interrupt to the central processing unit travel over different paths, or channels. A separate line or channel is provided to connect the interrupt pin of the peripheral device to an interrupt controller of the central processing unit, bypassing the switching fabric. There is no a priori assurance that all of the data will have been written to the memory before the central processing unit begins reading.
The inventor hereby incorporates all of the above referenced patents into this specification.

Enclosure for computer peripheral devices


An article of manufacture includes a jig including a flat surface with a curved groove therein; a light guide located within the curved groove, the light guide including an internal groove; and a bend-aid located in the internal groove of the light guide.

Field of the Invention
The present invention is related to methods and apparatuses for bending light guides for guiding light emitted by light emitting diodes (LEDs).
Description of the Related Art
Glass tubes filled with neon gas have been used to provide decorative, colored lights. For example, U.S. Pat. No. 5,001,613 describes a housing to protect neon tube lights. This is necessary because the glass tubes are fragile. Further, neon tube lights are difficult and costly to manufacture. Finally, neon tube lights consume a significant amount of power, and thus are costly to keep lit. Accordingly, alternative decorative lighting devices were desired.
The invention of LEDs allowed a low cost alternative to neon lighting. With regard to the power consumed, LEDs consume only 10% or less of a comparable neon tube light. However, the light from an LED needs to pass through a light guide to provide the same effect as a neon tube. To provide the same versatility as neon tubes, the light guides need to be able to be formed into a plurality of shapes, especially lettering. Conventionally, this has been done by heating a plastic light guide with a heat gun and then bending the hot light guide. However, this process is time consuming, difficult to repeat, and cannot provide light guides with a radius of curvature comparable to neon tubes.

Method and apparatus for bending LED light guides


The present invention relates to oleophobic filtration media including polymeric membranes and other substrates that are coated with polymerized substituted or unsubstituted para-xylene. A method of coating such substrates with polymerized substituted or unsubstituted para-xylene is also provided. The coated substrates possess both hydrophobic (water repellent) and oleophobic (oil repellent) properties.

The present invention relates to oleophobic filtration media including polymeric membranes and other substrates that are coated with polymerized substituted or unsubstituted para-xylenes. A method of coating such substrates with polymerized substituted or unsubstituted para-xylenes is also provided. The coated substrates possess both hydrophobic (water repellent) and oleophobic (oil repellent) properties.
Oleophobic filtration media, including membranes and substrates, are preferred for filtration of gases, in venting filters, and as gas vents. These oleophobic filtration media allow gases and vapors to pass through the filter while liquid water is repelled. Oleophobic filtration media are preferred for filters in healthcare and related industries, for example, as vent filters for intravenous (IV) fluids and other medical devices. In the health care industry, such filters must be sterilized before use.
Polytetrafluoroethylene (PTFE) has been the most common material in filters for gas venting. PTFE is chemically and biologically inert, has high stability, and is hydrophobic. PTFE filters therefore allow gases to be selectively vented while being impervious to liquid water. PTFE membranes can be sterilized for health-related applications with steam or by chemical sterilization without losing integrity.
Treating PTFE membranes with steam can cause pore blockage due to condensation of oil from the machinery that generates the steam. The resulting loss of air permeability reduces the membrane""s ability to serve as an air vent. Although chemical sterilization minimizes exposure of the membrane to oil, chemical sterilization uses toxic chemicals and can generate byproducts which cause waste disposal problems. Ionizing radiation has also been preferred for sterilization of materials in medical and biological devices. PTFE is unstable toward ionizing radiation. Irradiated PTFE membranes have greatly reduced mechanical strength and are generally not preferred for applications where they are subjected to even moderate pressures.
Perhaps the two biggest drawbacks to PTFE as a filter for venting gases are the high cost and the low air permeability of PTFE membranes. PTFE membranes are formed by extruding and stretching PTFE. Both the PTFE raw material and the processing to form the PTFE membranes are expensive. Further, the extruding and stretching processes preferred for forming PTFE membranes create membranes which have relatively low air permeability.
The oleophobicity of PTFE can be improved by impregnating or coextruding the PTFE with siloxanes (for example, U.S. Pat. No. 4,764,560), fluorinated urethane (U.S. Pat. No. 5,286,279), or perfluoro-2,2-dimethyl-1,3-dioxole (U.S. Pat. No. 5,116,650). Although the oil resistance of the PTFE is improved, the treated PTFE membranes are expensive, and air permeability remains fairly low. As a result, efforts have been made to identify alternative substrates which are less expensive and have higher air permeability than PTFE and which can be modified by coating to be hydrophobic and oleophobic.
Coating filtration substrates allows one to retain the desirable bulk properties of the substrate while only altering the surface and interfacial properties of the substrate. Coating substrates to increase their hydrophobic and oleophobic properties has not been practical, because the coatings can reduce permeability. Furthermore, many of the coating materials are expensive.
Scarmoutzos (U.S. Pat. No. 5,217,802) modified the surface of substrates made of nylon, polyvinylidene difluoride (PVDF), and cellulose by treating the substrate with a fluorinated acrylate monomer. The substrate was sandwiched between two sheets of polyethylene, and the monomer was polymerized by exposing to ultraviolet light. The resulting composite filters had hydrophobic and oleophobic surfaces. The air permeability of the filters decreases with time.
Moya (U.S. Pat. No. 5,554,414) formed composite filters from polyethersulfone and PVDF membranes with a method similar to that of Scarmoutzos. The resulting filters did not wet with water or hexane. The disadvantage of the Moya filters is that air permeability of the treated filters was lower than the untreated substrates, and the fluorinated monomer is expensive.
Sugiyama et al. (U.S. Pat. No. 5,462,586) treated nylon fabric and PTFE membranes with solutions containing two different preformed fluoropolymers. The treated filters were resistant to water and oils. The durability of filters coated with preformed polymers is often less than that for filters where the coating is formed by polymerizing a monomer on the surface of the substrate.
Kenigsberg et al. (U.S. Pat. No. 5,156,780) treated a variety of membranes and fabrics with solutions of fluoroacrylate monomers and formed coatings on the substrate by polymerizing the monomer. The coating conferred oil and water repellency onto the substrate. However, the airflow through the treated membrane was reduced, compared to the untreated membrane.
Hydrophobic media suitable for garments have been made by extruding mixtures of polypropylene or PTFE and the fluorochemical oxazolidinone as disclosed in U.S. Pat. No. 5,260,360. The media made by extruding tend to have relatively low air permeability.
In copending U.S. application Ser. No. 09/323,709 filed Jun. 1, 1999, oleophobic and hydrophobic filters are prepared by forming a polydimethylsiloxane coating on a polymeric substrate by polymerizing vinyl terminated siloxane with a crosslinker such as hydrosilicon in the presence of a catalyst.
In a first embodiment of the present invention, a coated filter is provided including a polymeric substrate and a coating, the coating including a polymeric para-xylene.
In one aspect of the first embodiment, the coating renders the coated filter permanently oleophobic.
In another aspect of the first embodiment, the polymeric substrate includes polysulfone. The polysulfone may include polyalkylsulfone, polyethersulfone, or polyarylsulfone. Alternatively, the polymeric substrate may include a polymer such as polyvinylidene fluoride, polyolefin, polytetrafluoroethylene, poly(tetrafluoroethylene-co-ethylene), acrylic copolymer, polyamide, nylon, polyester, polyurethane, polycarbonate, polystyrene, polyethylene-polyvinyl chloride, polyacrylonitrile, cellulose, or mixtures thereof. The polyolefin may include polyethylene, polypropylene, or mixtures thereof.
In a further aspect of the first embodiment, the polymeric substrate includes a porous membrane. The porous membrane may include an isotropic membrane.
In yet another aspect of the first embodiment, the porous membrane may include an asymmetric membrane. The asymmetric membrane may have a supporting structure, a first porous face having a first average pore diameter and a second porous face having a second average pore diameter, wherein an asymmetry between the first average pore diameter and the second average pore diameter is at least about 2:1, 5:1, 10:1, 20:1, or 200:1
In a further aspect of the first embodiment, the supporting structure includes an isotropic region adjacent the second porous face, the isotropic region having a substantially constant pore size, the supporting structure further including an asymmetric region adjacent the isotropic region. The isotropic region may extend through from about 5% to about 80%, or from about 15% to about 50%, of the supporting structure. The second average pore diameter may be between about 0.01 xcexcm and about 50.0 xcexcm, between about 0.05 xcexcm and about 20.0 xcexcm, or less than about 0.01 xcexcm.
In another aspect of the first embodiment, the polymeric substrate includes a material such as nonwoven material, woven material, or melt blown material.
In a further aspect of the first embodiment, the poly-para-xylene includes a polymonochloro-para-xylene or an unsubstituted poly-para-xylene.
In another aspect of the first embodiment, the coated filter further includes a support, wherein the coated filter is bonded to the support. The support may include a fabric. The support may include a material such as a woven material or a nonwoven material.
In a second embodiment of the present invention, a method of producing a coated filter is provided, the method including the steps of: providing a para-xylene dimer and a polymeric substrate; vaporizing the para-xylene dimer to form a para-xylene dimer vapor; pyrolyzing the para-xylene dimer vapor to form a reactive paraxylene monomer; depositing the reactive para-xylene monomer on the polymeric substrate, whereby a poly-para-xylene coating is formed on the substrate; and recovering a coated filter.
In one aspect of the second embodiment, the method further includes the steps of: providing a support; and bonding the coated filter to the support.
In another aspect of the second embodiment, the method further includes the steps of: providing a support; and bonding the polymeric substrate to the support.
The following description and examples illustrate a preferred embodiment of the present invention in detail. Those of skill in the art will recognize that there are numerous variations and modifications of this invention that are encompassed by its scope. Accordingly, the description of a preferred embodiment should not be deemed to limit the scope of the present invention.
There is a need for oleophobic and hydrophobic filtration media which are inexpensive and have high air permeability. Specifically, there is a need for a coating for membranes and other substrates that renders them oleophobic and hydrophobic. There is also a need for a more cost-effective process of making oleophobic filtration media.
By providing membranes and other substrates with parylene coatings, treated filtration media are obtained that have high permeabilities for air flow and reject liquid water, as evidenced by high water penetration pressures. The filtration media are useful, for example, as air filters or vent filters for intravenous (IV) or other medical devices. The critical surface tension for spreading (xcex3c), which is defined as the wettability of a solid surface by noting the lowest surface tension a liquid can have and still exhibit a contact angle (xcex8) greater than zero degrees on that solid, was dramatically reduced after treatment of the substrates according to a preferred embodiment.
The Substrate
The membrane or other substrate of the filtration media of preferred embodiments may be prepared from any suitable polymer. The polymer may be a homopolymer, copolymer, terpolymer, or more complex polymer. A single polymer or combination of two or more polymers may be preferred. The polymer may be subjected to a pretreatment, for example, sulfonation or grafting prior to forming a membrane casting dope, or may be subjected to a post-treatment, for example grafting or crosslinking, after a membrane is cast or a substrate is formed. There is no particular molecular weight range limitation for useful polymers.
In a particularly preferred embodiment, the polymer is a sulfone polymer such as polysulfone, polyethersulfone, or polyarylsulfone. Other suitable polymers include fluorinated polymers such as polyvinylidene fluoride (PVDF), polyolefins including polyethylene and polypropylene, polytetrafluoroethylene (PTFE or Teflon(trademark), poly(tetrafluoroethylene-co-ethylene) (ECTFE), acrylic copolymers, polyamides or nylons, polyesters, polyurethanes, polycarbonates, polystyrenes, polyethylene-polyvinyl chloride, polyacrylonitrile, cellulose, and mixtures or combinations thereof.
The substrates that may be coated may be in any suitable shape or form. If the substrate is a membrane, suitable forms include, but are not limited to, sheet and hollow fiber cast polymer membranes.
In general, the overall method of preparing a polymeric membrane includes the steps of providing a casting dope comprising a solution or stable colloidal dispersion. The casting dope is then cast as a thin film and exposed to a gaseous environment. Once the casting dope has been exposed to the gaseous environment, it is coagulated in a quench bath. After coagulating, the resulting polymer membrane may be rinsed in a suitable solvent, then air-dried or oven-dried.
Membranes in sheet form can be cast using any conventional procedure wherein the casting solution or dispersion is spread in a layer onto a nonporous support from which the membrane later can be separated after quenching. The membranes can be cast manually by being poured, cast, or spread by hand onto a casting surface followed by application of a quench liquid onto the casting surface. Alternatively, the membranes may be cast automatically by pouring or otherwise casting the solution onto a moving bed or belt. In casting, particularly in automatic casting, mechanical spreaders can be used. Mechanical spreaders include spreading knives, a doctor blade or spray/pressurized systems. A preferred spreading device is an extrusion die or slot coater which has a chamber into which the casting formulation can be introduced. The casting solution is then forced out of the chamber under pressure through a narrow slot. Membranes may also be cast by means of a doctor blade.
Generally, to produce a membrane, the cast film is exposed to a gaseous environment, such as air, sufficiently long to induce formation of surface pores of the desired size. Following casting and exposure to a gaseous environment, such as air, the cast dispersion or solution is quenched or coagulated. In a preferred embodiment, quenching is accomplished by transporting the cast membrane on a moving belt into the quenching liquid, such as a water bath. Membranes are recovered from the quench bath in the conventional manner by physical removal. The resulting membranes are typically washed free of solvent and may be dried to expel additional increments of solvent, diluent, and quench liquid.
Suitable membranes include both those membranes that are cast from a single polymer solution or dope, generally referred to as xe2x80x9cintegralxe2x80x9d membranes, as well as non-integral or composite membranes that are cast from more than one polymer solution or dope to form a layered or composite membrane. Composite membranes may also be assembled from two or more fully formed membranes after casting, for example, by lamination or other suitable methods. Filtration or exclusion media substrates other than membranes are also suitable for coating with parylene according to preferred embodiments. Non-limiting examples of other suitable substrates include hollow fiber media, melt blown or other nonwoven media, woven media, extruded media, and sedimented media.
The substrates that are suitable for coating in accordance with the preferred embodiments may include membranes having a symmetric or asymmetric pore structure. The term xe2x80x9casymmetricxe2x80x9d as used herein relates to a membrane possessing a pore size gradient or having a variation in pore size. That is, asymmetric membranes possess their smallest or finest pores in or adjacent to one surface of the membrane, generally referred to as the xe2x80x9cskinxe2x80x9d surface or xe2x80x9cshinyxe2x80x9d side of the membrane. The increase in pore size between the skin surface and the opposite surface of the membrane is generally gradual, with the smallest pore size nearest the skin surface and the largest pores being found at or adjacent to the opposite, coarse-pored surface, generally referred to as the xe2x80x9copenxe2x80x9d surface or the xe2x80x9cdullxe2x80x9d side of the membrane. Another variety of asymmetric membrane, commonly described as having a xe2x80x9cfunnel-with-a-neckxe2x80x9d structure, includes both an asymmetric region and an isotropic region, the isotropic region having a uniform pore size. The isotropic region typically extends from the skin surface of the membrane through about 5-80% of the thickness of the membrane, more preferably from about 15-50% of the thickness of the membrane. Another variety of asymmetric membrane has an xe2x80x9chourglassxe2x80x9d structure, wherein the largest pore sizes are on either surface of the membrane and the pores become gradually smaller in size towards the interior of the membrane.
The membranes of preferred embodiments also have a porous supporting structure between the two sides of the membrane. The nature of the porous supporting structure of a membrane may depend on the composition of the casting dope and the coagulation bath. The supporting structure can include, for example, closed cells, open cells of substantially the same pore size from one side of the membrane to the other, open cells with a gradation of pore sizes from one portion of the membrane to another, finger-type structures, generally referred to as xe2x80x9cmacrovoidsxe2x80x9d, and the like. Macrovoids typically vary substantially in size from the surrounding porosity, and generally do not communicate with surface pores. In a preferred embodiment, the porous supporting structure includes a network of structural surfaces capable of contacting a filter stream, defined herein as including any fluid substance, including liquids and gases, that passes through the membrane via the porous supporting structure.
Whether the membrane has an asymmetric or funnel-with-a-neck structure can depend upon several factors involved in the preparation of the membrane, including the type and concentration of the polymer, the solvent, and the nonsolvent; the casting conditions such as the knife gap, and the dope temperature; environmental factors such as the exposure time between casting and quenching, and the humidity of the exposure atmosphere; and the composition and temperature of the quench bath. In various embodiments, the asymmetry in pore size between the skin side and dull side of the membrane can range from about 1:2 or less, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, 1:10, 1:15, 1:20, 1:25, 1:30, 1:40, 1:50, 1:100, or 1:200 to about 1:500, 1:1,000 or 1:10,000 or greater.
Membranes that are suitable for coating in accordance with the preferred embodiments include, for example, membranes that typically possess porosities characteristic of ultrafiltration or microfiltration membranes. Membranes within the ultrafiltration range preferably possess molecular weight cutoffs of from about 10,000 Daltons to about 1,000,000 Daltons and can have pore diameters from about 0.001 xcexcm or less to about 0.050 xcexcm on the skin side of the membrane. Microfiltration membranes typically possess pore diameters of from about 0.01 xcexcm or less, 0.05 xcexcm, 0.1 xcexcm, 0.5 xcexcm, 1.0 xcexcm, 2.0 xcexcm, 3.0 xcexcm to about 5 xcexcm, 8 xcexcm, 10 xcexcm, 20 xcexcm, or 50 xcexcm or more on the skin side of the membrane.
Particularly preferred membranes include the highly asymmetric polyethersulfone membranes disclosed in U.S. Pat. No. 5,886,059 (incorporated herein by reference in its entirety). On one side of the PES membrane is a skin face having relatively small diameter pores while the opposite or dull face of the membrane has relatively large diameter pores. The difference in porosity between the skin face and the opposite face is preferably at least between 1:5 to 1:10,000. More preferably, the difference in porosity is between 1:10 or 1:20 and 1:50, 1:100, or 1:200. In addition, such membranes have a gradual change in pore size from the skin face to the opposite face. Thus, during filtration, larger particles can enter the membrane through the larger pores, but do not exit through the smaller pores. Because the larger particles do not become lodged at the outer surface, the membranes made by the methods provided herein are not easily clogged with large particles.
Hydrophilic membranes may also be coated according to the preferred embodiments. Such hydrophilic membranes include hydrophobic membranes that are post-treated with a surfactant or other material capable of rendering the membrane hydrophilic, as well as membranes prepared from a casting dope containing a hydrophilic material in addition to a hydrophobic polymer.
The filtration media of the preferred embodiments may include composite membranes. Composite membranes are membranes having multiple layers, and are useful in a variety of separation applications. In many cases, the various layers of a composite membrane each impart different desirable properties to the composite. For example, in some applications, an extremely thin membrane may have advantageous flow rates in separations of very small particles, gases, and the like. Yet such a thin membrane may be fragile and difficult to handle or to package into cartridges. In such cases, the fragile, thin layer membrane may be combined with a backing or with a stronger, more porous membrane, to form a composite having improved strength and handling characteristics without sacrificing the separation properties of the thin layer membrane. Other desirable properties imparted by laminating one membrane to another media may include increased burst strength, increased thickness, providing prefiltration capability, and providing an adhesive layer to ease assembly of a device.
Composite membranes may be prepared using lamination techniques, wherein sheets are layered together in a stack, optionally with one or more adhesive materials placed between the sheets to facilitate binding and lamination of the sheets to each other, and the stack is laminated into an integral composite membrane under application of heat and pressure. A different approach to making composite membranes is to cast or form one membrane layer in situ on top of another layer. The base layer may be a fibrous backing material or it may be a membrane. The composites may include, for example, composites having different layers of any of the foregoing media, composites having multiple layers of the same medium, or composites having layers of the same medium, but of different pore sizes, porosities, geometries, orientations, and the like. The composites may also include, for example, at least one of the foregoing filtration media with one or more additional layers of nonfiltration media such as backings or adhesives. The composite may be formed either before or after a membrane component is coated with parylene according to a preferred embodiment.
Composite filtration media of the preferred embodiments are not limited to composites including membranes. Composites including other filtration media, for example, nonwoven fibers or any other suitable non-membrane filtration media, are also contemplated.
In one type of composite, an oleophobic filtration medium of the preferred embodiment is bonded to a textile fabric or other woven or nonwoven material to form a layered fabric capable of excluding the passage of liquid while allowing passage of vapors and gases therethrough. Such a layered fabric can be useful in a variety of applications, as will be appreciated by those or ordinary skill in the art. Bonding an oleophobic filtration medium, such as a membrane, to a fabric may be accomplished by conventional adhesives, thermal bonding, and the like. In this embodiment, the filtration medium may be coated prior to, simultaneously with, or after the layering of the filtration medium with the fabric.
Any polymer capable of being processed into filtration media using conventional methods, such as, for example, melt-blown techniques, or that can be formed into a membrane by a casting or other process and that can be rendered oleophobic through coating with parylene is generally suitable for use in the preferred embodiments. Generally, oleophobicity is a characteristic of materials exhibiting repulsion to oils. Oleophobic materials repulse oils and possess a low surface tension value and are wetted by low surface tension liquids such as alcohol.
The Coating Material and Method
The membranes and other substrates of the preferred embodiments are generally provided with a parylene coating. Three types of parylene, available commercially under the GALAXYL trademark from Montell Polyolefins of Brussels, Belgium and distributed in the United States by PARA TECH Coating, Inc. of Aliso Viejo, Calif., may be preferred in various embodiments: GALAXYL(trademark) Parylene N, GALAXYL(trademark) Parylene C, and GALAXYL(trademark) Parylene D. GALAXYL(trademark) Parylene N is poly-para-xylene which is derived from para-xylene dimer. GALAXYL(trademark) Parylene C is poly-monochloro-para-xylene which is derived from monochloro-para-xylene dimer. Poly-monochloro-para-xylene coatings, such as GALAXYL(trademark) Parylene C, are preferred coatings for filters suitable for use in medical devices. Poly-monochloro-para-xylene coatings offer good chemical resistance and the ability to withstand repeated steam sterilization without significant coating degradation. Different parylene coatings may be preferred for different applications, as will be appreciated by one skilled in the art. Also, related compounds, such as, for example, meta-xylenes or ortho-xylenes, and various derivatives thereof may be suitable for use in certain embodiments.
The coating material of preferred embodiments is derived from one or more para-xylene dimers. The dimer in powder form is converted to a gaseous monomer that condenses and polymerizes on substrates at room temperature, forming a parylene coating. Unlike dip, spray or condensation coatings, a parylene coating does not run off the substrate or sag, is pinhole free, and does not bridge. Parylene may therefore coat a membrane evenly over the external surfaces of the membrane and the porous structures on the interior of the membrane. The thinnest parylene coatings that can be deposited using the vacuum application system described below are typically below 500 xc3x85 thick. Films having thicknesses from about 500 xc3x85 up to about 100 nm or higher may typically be deposited in preferred embodiments, however there is no absolute upper limit on film thickness. In preferred embodiments, the parylene layer deposited on the membrane substrate is from about 500 or less, 600, 700, 750, 800, 850, 900, 950 or 1000 xc3x85 thick to about 10, 15, 20, 25, 30, 35, 40, 45, 50, 60, 70, 80, 90, or 100 xcexcm thick or more. The larger the minimum pore size of the membrane to be coated, the thicker the coating that may be deposited without substantially affecting porosity.
In preferred embodiments, a single kind of parylene may be deposited in a coating. Alternatively, a mixture of two or more kinds of parylene may be deposited to form a single coating of mixed chemistries, or successive coating layers may be built up by depositing different layers having different chemistries. The preferred type and method of coating may vary depending upon the application, as will be recognized by one skilled in the art.
Some of the properties of parylene films include high reliability, true conformality, light weight, wide temperature range, stress-free, radiation resistance, low coefficient of friction, transparency, particle retention, virtually no outgassing, solvent resistance, low permeability to moisture and gases, acid and base resistance, fungus and bacteria resistance, extremely high dielectric strength, and high tensile and yield strength. Parylene is biocompatible, and is commercially available in a form having a USP XXII, Class VI biocompatibility rating.
Poly-para-xylene is generally applied to the substrate using a vacuum application system. A para-xylene dimer powder is typically placed in a vacuum system vaporization chamber and is heated to a temperature of +150xc2x0 C. to convert the powder into vapor form. Next, the dimer in vapor form may be converted in a pyrolysis chamber to reactive para-xylene vapor via pyrolysis at 650xc2x0 C. The reactive vapor may then be transferred to a polymerization chamber containing the membrane to be coated. The polymerization chamber may be maintained at ambient temperature. The reactive vapor typically polymerizes on the surface of the substrate, forming a uniform parylene coating. Parylene deposition systems are available from PARA TECH Coating, Inc. of Aliso Viejo, Calif.
In a preferred embodiment, deposition of the parylene layer is controlled so as to only partially coat the substrate. For example, a parylene coating may be applied on a membrane on one surface only in a layer not fully penetrating the pores through the entire thickness of the membrane. The parylene layer may also be deposited in a xe2x80x9cpolka dotxe2x80x9d geometry on a substrate. A xe2x80x9cpolka dotxe2x80x9d geometry is defined as a generally regular array of areas having a circular or other shaped profile including deposited parylene and separated from each other by areas of bare substrate with no deposited parylene. The xe2x80x9cpolka dotxe2x80x9d geometry is particularly useful in combination air vent and filter applications.
The thickness of the parylene film is typically controlled by controlling the length of time that the parylene is allowed to flow into the polymerization chamber. However, other methods may be preferred for controlling the coating thickness, as will be appreciated by one skilled in the art.
The Parylene Coated Substrates
The parylene-coated substrates of the preferred embodiments have high permeabilities for airflow and reject liquid water, as evidenced by high water penetration pressures. Airflow through a membrane can be measured in units of Gurley Flow. Gurley Flow is the time in seconds it takes 300 ml of air to pass through a 1xe2x80x3 diameter membrane under the force of a 5 oz weight. Gurley Flow may be measured using a Model 4110 GENUINE GURLEY(trademark) Densometer manufactured by Gurley Precision Instruments of Troy, N.Y.
Water penetration is determined by measuring the pressure in pounds per square inch differential (psid) required to force water through the membrane. Pounds per square inch differential is the difference in pressure existing on opposite sides of a membrane. In comparing two membranes having similar porosity, the water penetration pressure correlates with the membrane""s relative hydrophobicity, wherein a high water penetration pressure indicates that a membrane is more hydrophobic than a membrane having a lower water penetration pressure.


A configuration for charging in a telephone network, wherein a first subscriber pays for at least a part of the charges for connections established to him by a second subscriber. An intelligent network is linked to the telephone network and a service control point or a service node of the intelligent network exhibits control means for allocating charges to the first subscriber for connections established by the second subscriber to the first subscriber.

The invention relates to a configuration for charging in a telephone network such that a first subscriber pays for at least a part of the charges for connections established to him by a second subscriber, and to a method for operating such a configuration.
In modern business life, telephone contacts are of great importance and in recent years their significance has increased steadily in connection with the rapid development of modern telephony and also with the associated electronic data processing. There is no end to this development in sight.
In this connection, an increasing number of companies are practicing the setting-up of no-charge or low-charge call numbers such as the 0130 or 0800 service (free of charge), or the 0180 services (reduced charge). This practice is based on the concept that customers value no-charge or low-charge telephone contact as an essentially provided service of the corresponding company, and like to utilize it, whereas in many cases they otherwise would not conduct telephone conversations charged at normal rates, and then would probably not maintain the contact to the corresponding company.
However, setting up no-charge call numbers has the disadvantage that these call numbers are, in principle, accessible without restriction to anybody and can therefore be misused which, indeed, happens in practice. Thus, malicious callers can generate, possibly even by means of automatically generated calls, a considerable charge burden for the company that has set up a no-charge or low-charge call number. In addition, such practices have the consequence that the corresponding call number is occupied an unnecessary number of times and largely loses its value for the remaining customers.
It is accordingly an object of the invention to provide an improved generic configuration and a method for operating such a configuration which overcomes the hereinafore-mentioned disadvantages of the heretofore-known methods and devices of this general type in such a way that a misuse of the provision for establishing a no-charge or low-charge telephone contact with a particular subscriber can be largely prevented.
With the foregoing and other objects in view there is provided, in accordance with the invention, a configuration for charging in a telephone network wherein a first subscriber pays for at least a part of the charges incurred for connections established by a second subscriber to the first subscriber. The configuration includes a telephone network and an intelligent network linked thereto. A charge concession database is provided for storing identifiers selected from the group consisting of call numbers and call number ranges. Control means, configured within the intelligent network, is provided for allocating charges for a connection established from a second subscriber to a first subscriber by comparing a call number of the second subscriber with the identifiers. Additionally, an access device is provided for performing an operation selected from the group consisting of inputting, modifying, and deleting at least one of the identifiers stored in the charge concession database.
With the foregoing and other objects in view there is also provided, in accordance with the invention, a method for charging in a telephone network wherein a first subscriber pays for at least a part of the charges incurred for connections established by a second subscriber to the first subscriber. The method includes linking a telephone network to an intelligent network. Identifiers selected from the group consisting of call numbers and call number ranges are stored within a charge concession database. The intelligent network is provided with control means to allocate charges for a connection established from a second subscriber to a first subscriber by comparing a call number of the second subscriber with the identifiers. Additionally an access device is used to perform an operation selected from the group consisting of inputting, modifying, and deleting at least one of the identifiers stored in the charge concession database.
In accordance with an added feature of the invention, there is provided the essential idea of granting the authorization for no-charge or low-charge calls only to selected further network subscribers, and also of withdrawing this authorization again, if necessary, within a short time, on the basis of the capabilities of an intelligent network (IN) on the part of a first network subscriber. By limiting the authorized circle, a predetermined selection is made right from the start and thus misuse by unknown third parties is prevented. After a misuse by one of the privileged authorized parties has been found, the authorization can also be withdrawn again from him in a simple and rapid manner. Thus, a limited number of predetermined subscriber numbers or identifiers of authorized parties is continuously stored in the database which is why it can also be called a xe2x80x9cwhite listxe2x80x9d.
In accordance with an additional feature of the invention, the charge concession database can also be organized in the manner of a xe2x80x9cblack listxe2x80x9d, i.e. contain only call numbers or identifiers of subscribers to whom no freedom or concession of charges is to be granted. Here, too, continuous updating by deleting or adding new entries is possible analogously to the first type of embodiment. Compared with the first manner of the embodiment of the principle (white list), this variant has the advantage that the circle of authorized persons is not restricted a priori, i.e. new customers that have not yet been registered can also enjoy the concession. The price for this advantage in advertising strategy is that one has to accept a slightly higher risk of misuse.
Finally, it is also possible to store certain ranges of call numbers for authorized persons in the database, for instance certain initial numbers or sequences of initial numbers of call numbers or also certain other identification features.
So that a normal subscriber of a fixed network or mobile radio telephone network can control the charge concession for his customers, a trigger point for triggering access to the charge concession database must be set in his associated service switching point, via which trigger point the setting-up of a connection to the service control point (SCP) is activated to which the charge concession database is linked in the manner of a service data point (SDP).
If, in contrast, the first subscriberxe2x80x94as a subscriber of Universal Personal Telecommunication (UPT) or of a cordless telephony network (CTM)xe2x80x94has a call number of the intelligent network, then the service switching point of the caller, instead, sets up switching to a SCP, in connection with which the charge concession facility can be activated. The trigger point is omitted in this case. This similarly applies to the case where the first subscriber subscribes to an IN-controlled xe2x80x9cNumber Portabilityxe2x80x9d service, which should find widespread use in the future. Here, too, no special trigger point is required in the associated SSP because the associated switching point builds up a connection to the SCP, in any case, for such a subscriber.
In a so-called xe2x80x9cdistributedxe2x80x9d intelligent network, the functions described can be controlled by a service node (SN) since there is no service control point as such in this case.
There are basically two possibilities for establishing and managing the charge concession database: the more comfortable possibility, which, in any case, is preferred for large companies, consists of management via the Internet or, more precisely, via a so-called web Customer Service Control (CSC). The second possibility consists of utilizing a normal telephone as an access device for the database, where entries, changes or deletions can be carried out by means of the Dual Tone Multiple Frequency (DTMF) method. In both cases, the first subscriber must naturally authenticate himself in a suitable manner, for example by entering a password (especially in the case of Internet access) or a PIN (especially when using a mobile telephone for inputting) or by other identification means, for example also of a physical type (fingerprint, retina pattern).
In accordance with another feature of the invention, notification is provided to the caller concerning the granting of eliminated or reduced charges of a call. This is advantageous since such a reduction or elimination of charges can no longer be seen from the call number itself in the proposed solution. As a rule, a voice message will be generated for the caller for this purpose. In special cases, however, other ways of notification are also possible, for example by using the Short Message Service (SMS) for mobile radio subscribers.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a configuration for charging in a telephone network and method for operating such a configuration, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.

Configuration for charging in a telephone network and method for operating such a configuration