WO2005124504A1

WO2005124504A1 - External storage apparatus with serial ata type

Info

Publication number: WO2005124504A1
Application number: PCT/KR2005/000735
Authority: WO
Inventors: Jeong Hoon Lee
Original assignee: Colossus Corporation
Priority date: 2004-03-23
Filing date: 2005-03-16
Publication date: 2005-12-29

Abstract

The present invention relates to an external storage apparatus using serial ATA (Serial Advanced Technology Attachment, S-ATA) interface technology. More specifically, the invention relates to a network storage system, which can store (the storage capacity is variable along with the increase of capacity according to the manufacturing technology) up to approximately 1.6TB data (in case four hard discs are mounted) by providing an external housing separately, mounting hard discs inside the housing through a carriage panel, and providing a S-ATA interface main-board, which is electrically connected to the hard discs. In such a system, disclosed is an external storage apparatus of a serial ATA type comprising a housing structure, which is emphasized on easiness and convenience of construction, a cooling structure, which can exhaust and cool the heat generated by a long spell of operation of multiple hard discs, and an integrated cabling system, in which a hard disc can be connected to a host individually, or the mounted hard discs are connected to a host in one-to-one manner by one cable.

Description

Description EXTERNAL STORAGE APPARATUS WITH SERIAL ATA TYPE Technical Field

[1] The present invention relates to an external storage apparatus using serial ATA (Serial Advanced Technology Attachment, S-ATA) interface technology. More specifically, the invention relates to a network storage system, which can store (the storage capacity is variable along with the increase of capacity according to the manufacturing technology of a hard disc) up to approximately 1.6TB data (in case four hard discs are mounted) by providing an external housing separately, mounting hard discs inside the housing through a carriage panel, and providing a S-ATA interface main- board, which is electrically connected to the hard discs. In such a system, disclosed is an external storage apparatus of a serial ATA type comprising a housing structure, which is emphasized on easiness and convenience of construction, a cooling structure, which can more easily exhaust and cool the heat generated by a long spell of operation of multiple hard discs, and an integrated cabling system, in which a hard disc can be connected to a host individually, or the mounted hard discs are connected to a host in one-to-one manner by one cable. Background Art

[2] Storage is a place in which data accessible by a computer processor is stored in an electromagnetic form and generally classified into a first storage and a secondary storage. The first storages are various types of internal devices including RAM, and, on the other hand, in case of the secondary storage, data is stored in a hard disc, a tape, and an external device. The first storage is much faster than the secondary storage, however the secondary storage can store much more data than the first storage.

[3] On the other hand, according to the increase of applications which generate and use data, the requirement on storage for storing data also increases continuously, which encourages technical development of a secondary storage.

[4] Storage systems are categorized into a high-end field, which is a top model, and a low-end field according to capacity, stability, and completeness, and, up to date, storage industry has focused on the high-end field. However, recently, the potentiality of the personal storage market increases according as audio and video files can be stored in a PC, and a small company can be provided with a storage at a lower cost, so that the importance of the low-end field is emphasized. On the other hand, for specifications of a disc connection, the IDE (ATA) is used in the low-end field, and the SCSI method and the Fiber Channel interface are used in the high-end field. [5] The SCSI method and the Fiber Channel interface of the high-end field, having advantages in transmission speed and transmission distance, are expensive technologies which are aimed only for enterprise storage systems and thus not suitable for the low-end field.

[6] On the other hand, an external storage of the USB interface, and an IEEE 1394 interface device, for connecting peripheral devices (a digital camera, a digital camcorder, a DVD, and a music system) to a host PC, have a slow transmission speed and cannot construct a storage system which can backup, copy, and store data stably, so that they are not considered in the technical area to which the present invention is relevant.

[7] That is, the technical field of the invention relates to the ATA (Advanced Technology Attachment), called as the IDE (Integrated Drive Electronics), a standard interface used between a data bus of a computer motherboard and a disc storage apparatus of a computer, and, up to date, the parallel ATA (P-ATA) method, i.e. a parallel transmission method, is used.

[8] However, as the amount of data processing increases, the parallel ATA method encounters a limitation. That is, multiple data transmission lines are used in the parallel ATA method, so that severe signal interference is occurred, and cable allocation is difficult due to the thick and short transmission cable, thereby failing to further improve the data stability and speed thereof.

[9] As a standard interface technology in order to solve the problems, the S-ATA technology has been proposed. According to the technology, the operation principle and the internal structure are the same as those of the P-ATA, however, the S-ATA adopts a serial transmission method, which sends data one bit at a time, thus preventing signal interference between the signals and improving transmission speed by transmitting data faster. In addition, it provides the Hot-Plug function, enhances data stability by applying CRC to all the command, data block, and status signals when transmitting data, and makes the cable allocation easy and economical due to a thin and long cable.

[10] The technical area of the invention using the above advantages is a storage apparatus of low-end field which adopts the S-ATA technology, i.e., not an interface for connecting a hard disc inside a PC, but an external storage array apparatus formed of a RAID system of multiple discs. That is, in case of a host-embedded storage apparatus or an interface, a storage system is practically hard to construct on account of the troubles of installing the system by opening a PC case and the insufficiency of the available space in a PC itself. These are the obstacles to popularization of personal or small enterprise storage apparatuses, and the barriers to effective construction of a storage system. [11] The problems with the technologies to which the invention relates are summarized as follows.

[12] Storage technologies must consider storage capacity, transmission speed, stability, and cost. Especially, transmission distance, transmission speed, cable thickness, cost, memory availability, and stability are of importance in a disc connection interface. Needless to say, storage capacity is important, however, since the capacity of a disc memory is expanding continuously, the importance varies according to the purpose of a user using storage, and technical environments.

[13] Specifications for connecting discs are generally divided into the IDE (ATA) method and the SCSI method, and the Fiber Channel is a substitute interface for the SCSI method. The interface is divided into an internal type and an external type according to whether the storage apparatus is mounted in a host or implemented outside a host.

[14] Recently, PC users store various video and audio files in a PC and extensively use various applications which create and use data, so that the necessity of a storage apparatus grows day by day. On the other hand, in case where a user mounts a disc onto a slot in a PC, the user must disassemble the case of a PC and mount a disc onto a corresponding slot every time, so that, if a personal user does not have an extensive knowledge on a PC, the user may experience disadvantages in time and (mental/physical) labor. That is, an inexpensive storage apparatus having high transmission speed and large amount of storage capacity is required, for which a PC user does not need to disassemble a PC case and find a slot to connect inside a PC one by one, but can simply connect a disc to a PC with a predetermined cable. However, such a personal (or for a small enterprise) external storage apparatus is not publicized yet.

[15] Hereafter, the problems of a conventional internal storage apparatus are described, compared with the storage apparatus of the present invention.

[16] ® In order to mount a disc, a PC case must be disassembled. ® In order to mount a disc on a PC, the location of a slot in which the disc is inserted must be identified. ® Due to the thickness of a cable, a disc cannot be easily mounted on and installed in a narrow space. ® Generally, in case of an internal storage, when a CD-ROM and a writer are mounted while one disc is embedded, only one or two additional discs are allowed, so that storage capacity is limited. ® Constructing a RAID of discs is not easy. © In case of an internal storage, the storage cannot be connected to the other hosts, so that an efficient storage system cannot be constructed.

[17] On the other hand, the conventional parallel IDE (ATA) interface method has a problem in performance, and the SCSI or the Fiber Channel has an advantage in constructing a system, but the cost is too high for a personal user or a small enterprise to use.

[18] Conventionally, the P-ATA (Parallel ATA) is used. However, according to the increase of the amount of data processing, several problems of the P-ATA have been occurred. That is, the P-ATA of a parallel method uses several strips of data transmission line, so that, when transmission speed goes up, the magnetic field around the electric signal becomes strong, intensifying signal interference. This brings a limitation in transmission speed. Currently, the P-ATA has been developed as far as the ATA133 interface, supporting maximum transmission speed of 133MB/sec, however, in reality, lOOMB/sec is the limit. Furthermore, the P-ATA is a basic parallel method which has many data signal lines, and insulating lines are added between data lines in order to minimize the signal interference caused by magnetic field, so that the transmission cable is thick and short. Because of this, the P-ATA has serious drawbacks in cable allocation, ventilating structures inside a PC, and convenience for mounting a disc in a slot.

[19] In addition, the P-ATA does not support the Hot-Plug function. The Hot-Plug function supported in the USB and the IEEE 1394 is also called as the Hot-Swap, a function of replacing a hard drive, a CD-ROM drive, a power supply, and the like while a computer system runs, which enhances the completeness of the RAID function. A RAID is a function mainly used by a server which stores important data, a method of storing the same data in another place in duplicate when several hard discs are installed, which protects hard discs safely in a system running for an extended period of time without stopping, as in a server. The P-ATA can construct a basic RAID system, however it does not support the Hot-Plug function, so that, in case a hard disc is damaged, the disc is replaced after turning off the power of a server.

[20] Also, pointed out is the fact that the P-ATA applies CRC (Cyclic Redundancy Checking) only to data blocks, so that completeness of data is relatively low.

[21] On the other hand, in case of the SCSI and the Fiber Channel, the SCSI is known as an interface which allows faster and more flexible communications between a PC and a peripheral device such as a disc drive, a tape drive, a CD-ROM drive, a printer, and a scanner than the former interfaces, and currently supports up to 160MB/sec of transmission speed with a relatively long transmission distance of 25 m. In case of connecting an external storage apparatus to a host in the SCSI method, although a storage system can be constructed efficiently, the cost is too high for constructing a system in respect to performance (For example, the cost of a controller is high). Accordingly, the SCSI is not suitable for a home storage device, a personal storage device, and a small enterprise storage device. On the other hand, although the Fiber Channel is attractive in transmission speed (200MBps) and transmission distance (lOKm), since the technology is aimed only at an expensive enterprise storage system, constructing a system costs a great deal, so that the technology cannot be adopted for a personal, a small enterprise, and a home storage device. For example, in an environment suitable for a 200-thousand-dollar device, a storage apparatus, which costs 30,000 or 300,000 dollars, is not appropriate. Disclosure of Invention Technical Solution

[22] Accordingly, the present invention has been made in order to solve the above problems occurring in the art, and it is an object of the invention to provide an external storage apparatus, in which a disc can be attached and detached without disassembling a casing as well as to design a specially structured housing for easy installation.

[23] Furthermore, since four hard discs operate in the external storage apparatus of the invention, a cooling structure is provided in order to solve the heat problem accompanied by the operation of the hard discs.

[24] In addition, the external storage apparatus is intended for use in an individual, a small enterprise, a department of a big enterprise, a school, or a home, so that it is assumed to provide a storage capacity of as much as 1.6TB and a transmission speed of approximately 150MB/sec with a low cost for constructing a system. In order to accomplish the performance described above, the S-ATA interface technology is adopted.

[25] Also, the external storage apparatus is designed so as to allow attaching and detaching a disc regardless of On/Off state of the power of a host by performing the Hot-Plug function, and configured to have a separate power supply so as not to rely on the power supply of the host. In order to enhance the performance of storing data, diverse RAID configurations are taken into account.

[26] Furthermore, utilizing the mounted four hard discs effectively, a cable structure which allows connecting each hard disc to each of multiple hosts (for example, 2 - 3 hosts) individually or connecting four hard discs to one host, in other words, a cable structure which connects each of the four hard discs to each host using an individual cable attached to the array of four hard discs or connects the four hard discs to a host using one integrated cable, is selected as a very important task. The final goal of the invention is constructing an effective storage system, and the storage apparatus of the invention is eventually assumed to be connected to a host, so that the structure and the characteristic of a cable which provides a connection to a host are deeply considered by the inventor. On the other hand, in order to connect compatibly an external storage apparatus of the S-ATA interface to a host of the P-ATA method (the main-board does not support the S-ATA interface), a serial ATA controller of the PCI method is required, so that the fact that the controller must have a proper relationship with the integrated cable provided by the invention is also considered.

[27] In order to accomplish the above objects, according to one aspect of the invention, there is provided an external storage apparatus communicating with a host using the serial ATA, an external storage apparatus of the serial ATA type comprising: a storage housing in which an external housing, an internal housing, a rear panel, and a front cover are assembled in one set; multiple hard disc carriage panels which receive and firmly attach hard discs, and carry and insert the hard discs into the housing; a host connector receiver which includes a single connector receiver corresponding in one- to-one manner to each inserted hard disc independently and an integrated connector receiver which connects embedded hard discs, which integrated into one connector through a data bridge between the hard discs, one host cable; a serial ATA main-board inserted into the rear portion of the inside of the housing, which is electrically connected to the hard discs received by the carriage panel inserted inside the housing and communicates with the host through the single connector receiver and the integrated connector receiver; a cooling fan which is configured to cool down the temperature of the inside of the housing which goes up due to the operation of hard discs; and an external DC adapter which supplies driving power to the internal devices inside the housing, including the serial ATA main-board.

[28] In addition, the external storage apparatus of the serial ATA type of the invention preferably enables a first group of ventilating holes to be formed at the front portion of both sides of the external housing.

[29] The structure of the internal housing comprises:

[30] a top surface which is LI in width and L2 in length; a left surface connected to the front cover connector which is protruded by d3 toward the front, in which the rear portion is extended by dl toward the rear of the housing, bent 90 degrees toward the external housing, and extended by d2, and the front portion is bent 90 degrees toward the external housing without extension of dl and extended by d2; and a right surface which is formed of a structure symmetrical to the left surface, and secures ventilating space so that the air inside the housing may flow back and forth, and left and right, and communicates with the ventilating hole group of the external housing.

[31] In addition, the internal housing preferably includes multiple guide rail grooves which guide the carriage panels into the internal housing, and multiple carriage panel supports which firmly support each carriage panel to the corresponding layer.

[32] The carriage panel of the invention comprises:

[33] a hard disc receiver, hard disc side supports which extend upwardly from both sides of the hard disc receiver with them being bent 90 degrees and support the sides of a hard disc, a hard disc connector which fixedly attaches a hard disc to a carriage panel, and a connector which connects the carriage panel to the housing by connector means, in which the hard disc receiver has a second group of ventilating holes formed thereon so as to exhaust the flow of the heat generated by the hard discs.

[34] The external storage apparatus of serial ATA type of the invention further comprises a display means which displays the operation status of the embedded hard discs and the power status, and, in the case where the internal housing is configured so as to include four layers, provide four carriage panels, and mount four hard discs, this configuration is expected to be the most appropriate embodiment considering costs, configuration, purchasing ability of the target consumers, and required storage capacity.

[35] On the other hand, the cooling fan of the invention is a dual fan structure preferably comprising two cooling fans which adopt the ball bearing method.

[36] The present invention relates to an external storage apparatus communicating with a host using the serial ATA, which comprises a serial ATA main-board electrically connected to a single connector for connecting a hard disc to a host in one-to-one manner and an integrated connector for connecting hard discs to a host in N-to-one manner (N is an integer greater than one, the number of mounted hard discs), secures ventilating space by defining a certain gap between the internal housing and the external housing, allows a first group of ventilating holes to be formed at the front portion of both sides of the external housing, allows a second group of ventilating holes to be formed on the carriage panel for carrying the hard disc into the internal housing, and cools down the temperature of the inside of the housing by two cooling fans.

[37] The external storage apparatus further comprises a switching means which selects one of the single connector and the integrated connector, and, the operation of the switching means enables the integrated connector to be switched off when the single connector is used, and the single connector to be switched off when the integrated connector is used, thereby preventing the data interference between the single connector and the integrated connector, which is considered important in the present invention.

[38] Brief Description of the Drawings

[39] Further objects and advantages of the invention can be more fully understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

[40] FIG. 1 is a perspective view schematically showing an internal configuration of the invention;

[41] FIG. 2 is a perspective view showing an external housing according to one embodiment of the invention;

[42] FIG. 3 is a perspective view showing an external housing of FIG. 2;

[43] FIG. 4 is a perspective view showing an internal housing inserted into the external housing of FIG. 3;

[44] FIG. 5 is a perspective view showing a carriage panel which carries a hard disc into the internal housing;

[45] FIG. 6 is a perspective view showing a connector means which connects the carriage panel to a corresponding layer of the internal housing;

[46] FIGS. 7 and 8 are cross-sectional views showing the operation principle of the connector means in FIG. 6;

[47] FIG. 9 is a perspective view showing a rear panel in FIG. 2;

[48] FIG. 10 is a perspective view showing a front cover in FIG. 2;

[49] FIG. 11 is a perspective view showing a base panel in FIG. 2; and

[50] FIG. 12 is an exploded perspective view of FIG. 2. Best Mode for Carrying Out the Invention

[51] The prefened embodiments of the present invention will be hereafter described in detail with reference to the accompanying drawings.

[52] The detailed descriptions on known function and constructions which unnecessarily obscure the subject matter of the present invention and are obvious to an ordinary person skilled in the art will be avoided hereinafter.

[53] The serial ATA interface is applied to the present invention.

[54] ® The S-ATA transmits data one bit at a time, so that the amount of data transmitted at a time is less than that of the P-ATA. However, data is transmitted very fast, so that the basic speed of transmission is faster than that of the P-ATA eventually. For example, the P-ATA transmits 32 bits of data at one time at the speed of 25MHz, so the transmission ratio of the P-ATA is only lOOMB/sec, on the other hand, the S- ATA transmits one bit of data at the speed of 1,500MHz, thereby recording the transmission ratio of 150MB/sec, faster than that of the P-ATA. Furthermore, the S- ATA has a characteristic of being free from signal interference. In addition, ® the S- ATA of the invention is a serial method, so that the number of pins and the size of a cable are considerably small and the length can be extended more. Therefore, cable allocation, internal ventilating structure, and mounting performance are greatly improved. ® In order to install and detach a hard disc while a power source is connected, the Hot-Plug function is implemented by making the length of the copper power lines of an S-ATA connector different. The S-ATA connector is configured such that, when a connector is connected, the longer line of the power line is contacted to the power source, and the shorter one is contacted to data. When the connector is disconnected, the data line is removed first, and the power line is removed last, so that the data stored in the hard disc is protected safely.

[55] The heat generated by the hard disc of the invention, and the principle of cooling the heat

[56] The number of hard discs mounted on the storage device of the invention reaches up to four in the selected optimum embodiment. The heat generated from the four hard discs is enormous, and the internal space is narrow due to the size of the apparatus of the invention, so that the implementation of an effective cooling system is very important. In order to solve the problems, the chassis of the housing of the invention is made of aluminum (Aluminum has a good heat generation effect, and is light additionally), not of ordinary iron, and 40 mm cooling fans are allocated at the rear of the housing for direct cooling effect. Furthermore, although the amount of the wind from the one 40 mm fan is sufficient considering the size of the product itself and the others, in order to facilitate flow of air more, two cooling fans are used. Also, in order to facilitate flow of air all the more and to maximize the efficiency of the cooling fans, the housing of the storage apparatus is divided into an external housing and an internal housing and assembled together, and, on the other hand, a ventilating space is secured between the external housing and the internal housing with various perforated ventilating holes, thereby enabling effective cooling. These are explained in detail in the folio wings.

[57] The specifications and performance of an S-ATA cable, and the principle of the integrated cable of the invention.

[58] The S-ATA transmits data through a two-wired electric line, four lines in total which are divided into transmitting lines for sending data and receiving lines for receiving data. In addition, even though the number of wires for transmitting data is four, the number of the pins of a connector increases to seven due to the earth wire. The earth wire prevents the S-ATA signal, which is operating at a very high clock of 1.5GHz, from being intervened by the noise from outside. Securing ultimately the purity of signal by a shielding structure, the length of an S-ATA cable is extended to a maximum of 1 m.

[59] PCI controllers

[60] In the case where an S-ATA connector is not embedded in the main-board of a host to which the external storage apparatus of the invention is connected, a separate S- ATA PCI controller must be installed at the storage main-board of the invention. Needless to say, an S-ATA PCI controller itself is a publicized technology. For example, in the case where four hard discs are mounted, a serial ATA controller of a maximum of four channels must be installed, however, in order to use the integrated cable interface of the invention, a PCI controller provided with an integrated cable interface must be used. In this case, only the serial ATA PCI controller of the invention can support both a cable for single channel and an integrated cable.

[61] Methods of connecting to a host

[62] The method of connecting the storage apparatus of the invention to a host is generally divided into two ways. The first one is a method using an interface for an integrated cable, and, for this configuration, an S-ATA PCI controller, which provides an integrated cable and an interface for the integrated cable, is needed, as explained above. The second one is a method of connecting a general S-ATA PCI controller to each hard disc in one-to-one manner through an S-ATA cable. In this configuration, in case of mounting four HDDs inside the housing of the storage apparatus of the invention, four S-ATA cables are needed, and the PCI controller must support four- channel S-ATA.

[63] However, the publicized PCI controllers currently distributed are manufactured on the basic assumption that S-ATA HDDs are connected inside (not an external type) a host (a computer, etc.). Thus, in case of a PCI controller supporting practically a four- channel S-ATA, not a product is equipped with two or more external interfaces. In case of using the above PCI controller or an S-ATA connector embedded in the main-board of a host, four S-ATA HDDs must be connected externally in order to be connected with a storage apparatus of the invention, so that the internal interfaces must be extended to the outside by mounting brackets additionally.

[64] Principles of RAID configuration

[65] RAID is the abbreviation of Redundant Array of Inexpensive (or Independent) Disks, and a RAID system allows a set of several drives to be treated as one storage apparatus, prevents data from being lost when an error occurs, and allows each drive to operate independently. The methods of configuring a RAID such as RAID 0, RAID 1, RAID 2, RAID 3, RAID 4, RAID 5, RAID 6, RAID 7, RAID 0+1, RAID 50, and RAID53 have been developed continuously in a new mode, and, among the methods, the other methods except RAID 0, RAID 1, RAID 0+1, and RAID 5 are barely used.

[66] RAID level 0, called as a stripping method, uses at least two or more hard discs, and, when writing data continuously, writes and reads different data to and from each hard disc alternatively at the same time. This method is the RAID system having the best performance of the several RAID levels, in which input and output take place at multiple hard discs simultaneously, so that the amount of transmitted data increases according to the number of added hard discs. However, in the case where only one of the hard discs of the RAID 0 system has a problem, the data stored in the other hard discs is affected all together. Because of this, RAID 0 method has a strong tendency of not being considered as a real RAID system and is not very often used for expensive servers or workstations which need safety of data, but used in combination with RAID 5 or RAID 0+1 which provides safety together with excellent performance.

[67] RAID Level 1, called as a Mirroring method, uses at least two or more hard discs similar to the Stripping method, and stores the same data in each disc. Compared with the RAID 0, this method is developed in order to secure safety rather than speed of a hard disc, so that, although one of hard discs is damaged, since another disc having the same contents exists, data can be recovered perfectly. However, since this method writes the same data simultaneously, no matter how many hard discs may be installed, the method is performed only as if one hard disc is used.

[68] RAID Level 0+1, a combined type of the Stripping method and the Mirroring method, is a RAID system developed in order to satisfy both the excellent performance of the Stripping and the high safety of the Mirroring. If the Stripping method is used with two hard discs, the Mirroring side also must have the same number of hard discs. Accordingly, minimum four hard discs are needed.

[69] RAID Level 5 method is a parity dispersion recording method which records parity information while stripping data inside of each configured HDD itself, so that additional hard disc for recording parity information is not needed. In addition, since input/output can be performed fully in parallel with each disc, writing and reading at the same time, input/output of data is very fast and stability of data is also rather high, so that RAID Level 5 method is the most widely used RAID method currently. RAID level 5 distributes parity information to all discs when recording parity information. The discs in charge of parity information do not creates bottlenecks, so that RAID level 5 is fast when writing small and frequent data of a multiprocessor system, however, in case of only reading data, the parity information must be skipped in each drive, so that RAID level 5 is considerably slow compared with RAID level 4 array.

[70] In the invention, RAID 0, 1, 0+1, and 5 can be configured according to the S-ATA controller being used, and, when two or more users share one storage apparatus of the invention, each of two users occupies two hard discs receptively, and thus RAID 0 or 1 can be configured. If one user occupies three hard discs, RAID 5 can be configured, and the other user can use the other hard disc only for ordinary purposes, not for configuring RAID.

[71] FIG. 1 schematically shows an internal circuit configuration of the invention.

[72] An ordinary value of DC 12V power is switched on through an external adapter and input to the inside of the housing of a storage apparatus. The external power being input is supplied to a serial ATA main-board through a regulator, hard discs as driving power through a hard disc power interface, and two fans and a display means LED which are installed in the housing.

[73] The main-board including a hard disc power interface and a hard disc data interface is connected to a host through a PCI controller interface. As explained above, the method of connecting to a host is determined by whether a single interface controller is used, in which a host is connected to a hard disc in one-to-one manner, or an integrated interface controller is used, in which four hard discs are integrated by an integrated connector and Data Bridges of individual connectors. At this point, a switching means which selects either a single connector or an integrated connector is further comprised. By the operation of the switching means, the integrated connector is switched off when the single connector is used, and the single connector is switched off when the integrated connector is used, thereby preventing the data interference between the single connector and the integrated connector. The switching means is constructed in the form of a switching chip-set, in which the single connector turns off automatically when the integrated connector is connected, and the integrated connector turns off automatically when the single connector is connected. In the case where the switching means is constructed as a deep switch a connector is selected by the manual operation of a user.

[74] In the present invention, both of the two interface controllers are comprised, so that a user can use one integrated interface controller conveniently, or, in the case where only one hard disc is mounted or in case two or more users use the storage apparatus of the invention, the single interface controller can be used independently.

[75] Also, two fans inside the storage apparatus of the invention functions to cool the heat generated by multiple discs. Preferably, the storage apparatus is constructed such that the operation status of hard discs is recognized through an activation indicator, and a heat detecting sensor is included in each hard disc, so that, according to the amount of heat and the status of disc operation, the operating speed of the cooling fans is controlled by an RPM controller which controls RPM of the cooling fans in accordance with the value input through the heat detecting sensor. Accordingly, the generation of the noise accompanied by the operation of the cooling fans can be suppressed, and stability can be secured more easily by the control of heat generation.

[76] FIG. 2 shows a housing 1 of an external storage apparatus according to one embodiment of the invention. FIG. 3 shows an external housing, FIG. 4 shows an internal housing, FIG. 5 shows a carriage panel which carries a hard disc to the internal housing, FIGS. 6 to 8 show a connector means which fixes and connects the carriage panel to the internal housing, FIG. 9 shows a rear panel; FIG. 10 shows a front cover, FIG. 11 shows a base panel, and FIG. 12 shows an exploded perspective view of the housing, respectively. The systematic construction relationships between the parts are described in brief below. The internal housing 20 comprises a main-board (not shown), including a circuit configuration, a connector, and a controller, and cooling fans (not shown) at the rear side is inserted into the external housing 10, and a rear panel 40 is attached to the rear side of the external housing 10, in which connector receivers 42, 43, exhausting outlets 41 of cooling fans, an input 44 of an external power, and a power on-off switch 45 are formed. Inside the internal housing 20, four layers are formed so that carriage panels 30 may be inserted in order to transfer hard discs to the internal portions of the layers, and a front cover 50 comprised of a display 51 covers the internal housing 20. Then, the above constitutional elements are assembled on the base panel 60 of the housing, connected by a certain connector means, and separated by disassembly of the connector means.

[77] As shown in FIG. 3, the external housing 10 is formed of an aluminum plate in a "D" shape and connected to the base panel 60 by connector means 12. On the other hand, at the front portion of both sides of the external housing 10, multiple small ventilating holes are constructed in one group for the purpose of exhausting the air inside the housing 10 to outside (Hereafter refer to as a first group of ventilating holes). On the other hand, on the top surface of the external housing 10, a connecting bar (not shown) is constructed in order to connect the external housing firmly to the internal housing, and at the upper portion of the rear inside, a main-board fixing bar (not shown) which can fix the main-board from the top is installed. The main-board is fixed at the bottom by a main-board fixing bar 62 which is installed at the base panel 60.

[78] FIG. 4 shows the structure of the internal housing 20 in detail. The internal housing 20 basically has a "D" shape, similar to the external housing 10, and inserted in and connected to the external housing 10.

[79] First, a connection hole 26 is provided on the top surface 21 of the internal housing so that the connecting bar of the external housing may be inserted, and the form of the top surface 21 is a square of LI X L2 (width X length). Looking into both sides of the internal housing, the left side 22 is extended by dl toward the rear of the housing, resulting in the width of "LI + dl" bent 90 degrees from the direction of the width toward the side of the external housing, and extended by d2. The length of the end portion in the front direction of the housing is not extended, and the end portion is bent 90 degrees toward the side of the external housing by d2 in length. Also, at the end portion of the upper and lower portion of the left surface 22, a front cover connector 25 protruded by d3 in length is formed so as to attach the front cover 50. In addition, at the front of the internal housing, the end portion is bent 90 degrees by d2 in length, and then bent again 90 degrees toward the rear by predetermined length. On the other hand, the right side 28 of the internal housing 20 is formed symmetrically to the left side 22, so that the structure is same.

[80] The structure of the internal housing 20 explained above is constructed to form a certain space at the front, rear, and both sides when inserted into the external housing 10 and connected to the external housing 10, so that the air inside the housing 1 may be circulated between them freely. That is, if the height of each side is L3, a ventilating space of "(LI + dl) X d2 X L3" is secured at both sides, "L2 X L3 X dl" at the front, and "L2 X L3 X d3" at the rear. On the other hand, from the ventilating space, especially at the front and the rear side, the volume occupied by the other portions of the construction (for example, connector means of the carriage panel, a main-board or cooling fans) can be subtracted as a matter of course if the volume is small.

[81] On the other hand, at both sides 22, 28 of the internal housing 20, guide rail grooves 23 which guide the carriage panel 30 are multiply formed, and, under the guide rail grooves 23, multiple carriage panel supports 24 are provided, which firmly supports the carriage panels.

[82] FIG. 5 shows a carnage panel 30 according to the invention, comprising a hard disc receiver 31, a second group of ventilating holes, hard disc side supports 33, hard disc connection holes 34, and carriage panel connectors 35.

[83] After a hard disc being received on the hard disc receiver 31, and the hard disc is connected to the carriage panel 30 by inserting predetermined connector means into the hard disc connection holes 34 formed at the hard disc side supports 33 through the hard disc side supports 33, which are formed by bending both sides of the hard disc receiver 31 90 degrees upward, the carriage panel 30 plays a role of carrying a hard disc into the internal housing 20 through the guide rail groove 23, and is fixed to the corresponding layer and supported by the carriage panel support 24. On the other hand, a hard disc generates a lot of heat when operating, so that multiple ventilating holes (the second group of ventilating holes) are formed on the surface of the hard disc receiver 31 in order that the heat generated from the hard disc can be exhausted through the ventilating holes.

[84] Then, the convection of the heat generated by the operation of hard discs inside the housing 1, i.e., the flow of air, is processed such that the air circulates inside the housing 1 through the ventilating space between the external housing 10 and the internal housing 20, and the second group of ventilating holes formed at each carnage panel. The air is exhausted outside the rear panel 40 of the housing through the two cooling fans (not shown) installed inside the housing. Furthermore, through the first group of ventilating holes 11 formed at the front portion of both sides of the external housing 20, the heat is exhausted outside or the cold air of the outside flows in.

[85] FIGS. 6 to 8 shows a carriage panel connector means 36 which connects the carriage panel 30 to the internal housing 20 through aligned holes of the carriage panel connection hole 27 of the internal housing 20 and the carriage panel connector 35 of the carriage panel 30, after the carriage panel 30 is inserted inside each layer of the internal housing 20 through the guide rail groove 23.

[86] The carnage panel connector means 36 provides an environment in which a user can mount the carnage panel 30 on the internal housing 20 easily. That is, the carriage panel connector means 36 comprises a connector means body 37, a connector means stopper 38, and a connector means insert 39, in which the connector means body 37 includes a handle, a stopper "X", and an insertion body in one piece, and the connector means insert 39 divided into three parts is constructed so as to be spread and shrunk by the forward and backward operation of the insertion body. If a user aligns the carnage panel connection hole 27 and the hole of the connector 35 of the carriage panel 30, inserts the carriage panel connector means 36 into the hole, and pushes the handle with power, the insertion body of the connector means moves forward until the stopper "X" is latched to the connector means stopper 38, and the connector means insert 39 is inserted into the hole completely. (The connector means insert 39 made of an elastic member is formed such that, although the diameter at the initial insertion position is shorter than the diameter of the hole, the diameter gradually grows to be longer than the diameter of the hole, so the initial insertion is accomplished naturally) At this time, the shrinking elasticity of the connector means insert 39 is suppressed by the connector means body 37, and the diameter of the connector means insert 39 inside the hole grows longer than the diameter of the hole by contacting close with the connector means body 37, so that the carnage panel 30 is fixed inside the conesponding layer of the internal housing 20. On the contrary, if the stopper "X" moves above the connector means stopper 38 by pulling the handle of the carriage panel connector means 36, the connector means insert 39 and the connector means body 37 are not contacted any more, and the shrinking elasticity of the connector means insert 39 is in effect again, so the carriage panel connector means 36 is extracted from the hole.

[87] FIG. 9 shows a rear panel 40 which is connected to the rear side of the external housing 10, comprising an exhausting outlet 41 of the cooling fan, a single connector receiver 42, an integrated connector receiver 43, an external power input 44, and a power on-off switch.

[88] On the rear panel 40, a single connector receiver 42 is prominently formed, which conesponds to a single connector (not shown) connected to a serial ATA main-board (not shown), and an individual cable for a single connector is connected to each connector of the prominent single connector receiver 42. A cable for an integrated connector is connected to the integrated connector receiver 43 which is connected to an integrated connector, and the storage apparatus communicates with a host.

[89] In the structure of the connector and the cable which are used in an embodiment of the invention, the pin array includes 20 pins in total, in which five pins per hard disc are allocated for data transfer of the four hard discs of the serial ATA 1 - 4, and the configuration of each pin is "TX+, TX-, RX+, RX-, and Ground X 4 group = 20 Pin" Four grounds are required internally in a cable in order to support the Hot-Plug function which allows connecting to a host while system power is turned on. In order to shield noise mostly generated by the connecting portion of a cable, a connector is structured in forms of being shielded by each group (five pins are allocated per group), preventing the distortion of signal which is generated by physical contacts of several pins or a near-end crosstalk within a short distance.

[90] In this embodiment, two cooling fans are installed inside the housing 1, and two conesponding exhausting outlets 41 are formed at the rear panel 40. When a storage apparatus is used for a long time (generally, chances to be used for long are frequent), if only one cooling fan is installed, may arise a fatal problem which cannot cool down the heat of hard discs inside the housing 1 effectively with the breakdown of the fan. In addition, although the cooling fan may operate properly, installing two cooling fans is preferable considering the number of hard discs (in this embodiment, the number of hard discs is four).

[91] In addition, the ball bearing method is adopted for the construction of the cooling fan. In case of the sleeve bearing method distinguished from the ball bearing method, lubricant is used when a fan rotates, and if a fan is used for long hours, the lubricant is used up, generating noise. In the field of bearings used for constructing a cooling fan, the life-span of a cooling fan of the ball bearing method is about 45,000 - 80,000 hours when the cooling fan is used 24 hours continuously in a room temperature of 25 degrees Celsius. On the contrary, in case of the sleeve bearing method, a fan being used 24 hours continuously in a room temperature of 25 degrees Celsius, the life-span is reported to be about 30,000 - 45,000 hours, and the ball bearing is reported to be superior in noise suppression. In this embodiment, in order to reduce noise, the size of a fan is down-sized to 40 X 40 X 10 (width X height X length, mm), and an appropriate practical value is obtained by setting the operation RPM to 4,200 - 6,000, the amount of airflow to 4.70 - 7.20 CFM (Cubic Feet per Minute), the noise generation to below 25bd, and the voltage of the input power to DC 12V. However, the method constructing a cooling fan and a specification itself are not the main idea of the invention, and do not have special meaning to those skilled in the art.

[92] FIG. 10 shows the front cover 50 according to one embodiment of the invention.

[93] The material of the front cover 50 may be an aluminum plate, transparent glass, or a synthetic resin. Only at the lower portion of the front cover 50, a display unit 51 is formed in perforating holes so that a user may know the operation status of a display means (LED) which is fixed to a display means fixing bar 61 of the internal housing 20 and connected to the internal housing 20 by a front cover connector 52 and a certain connector means 53. FIG. 11 shows a base panel 60 according to one embodiment of the invention.

[94] A display means (LED) fixing bar 61 is provided at the front portion of the base panel 60, so that a display means (LED) (not shown), which is electrically connected to the main-board and the external power supply and displays the operation status and power status, is fixed. On the other hand, at the rear portion of the base panel 60, a main-board fixing bar is formed, which fixes the lower portion of the main-board by connector means.

[95] FIG. 12 shows assembly and disassembly of each part of the storage apparatus according the invention.

[96] The specific construction of each part of the invention such as an external housing 10, an internal housing 20, a carriage panel 30, a rear panel 40, a front cover 50, and a base panel 60 is explained above, and each part of the construction is assembled by various connector means. Generally, a screw or the like is used as a connector means, however, the other various means will be contrived, and a connector means is not the main idea of the present invention and easy to construct, so that it is not explained in detail.

[97] On the other hand, an additional software support will be required in order for effective operation of the external storage apparatus of the invention, typically a software that informs of the number and information (capacity, manufacturer, etc.) of serial ATA hard discs and displays the type of RAID configuration (Level, and whether the operation is normal), and a software for managing internal configurations of the housing, a controller, and an integrated cable of the invention. However, needless to say, those softwares are not the main idea of the invention.

[98] The embodiments described above are only to illustrate the invention, and the applications of the invention are not restricted by the embodiments. Industrial Applicability

[99] As described above, the invention provides an external storage apparatus, in which hard discs can be attached and detached, so that a user does not need to suffer from troubles of disassembling a PC casing or arranging cables to find a slot particularly and may apply the storage system to a PC easily.

[100] In addition, by applying the serial ATA interface, a transmission speed of 150MB/sec is provided, and an effective RAID can be constructed using a maximum of four discs.

[101] Furthermore, the cable is thin and the connector is small, so that installing and ananging will be easier, and the effect of smart appearance can be obtained. On the other hand, since the cable has a margin of about 1 M, installation of the external storage apparatus in a practical manner will be more flexible.

[102] Also, by adopting an independent power supply, not depending on the power of a PC or a host, although the power of a host is turned off, the operation of discs is not affected, and the serial ATA interface provides the Hot-Swap technology, so that a disc can be attached and detached while the power of a host or the power of the storage is turned on. This provides a user with convenience and a system will be highly stable.

[103] On the other hand, the invention has strength in applying CRC (Cyclic Redundancy Checking) which confirms the existence of enors in a data transmitted through communication links. For example, when a data is transmitted, a command, a data block, and a status field are moved in a bundle, and CRC is applied only to the data block in the conventional P-ATA method, however a SATA storage apparatus of the invention applies CRC to all the three signals, enhancing the stability of data by supporting the high frequency clock of 1.5GHz.

[104] Looking into the specific effects of the external housing of the invention in more detail, the apparatus is designed such that a user can attach and detach hard discs easily. For example, the structure of the guide rail of the internal housing and the connecting structure of the carriage panel provide an environment for easy installation of hard discs.

[105] In addition, as shown in the embodiment, the amount of heat generated by the operation of four hard discs must be huge, so that the required cooling solution has excellent ventilating and cooling effects through specially designed two cooling fans, a first group of ventilating holes at both sides of the external housing, a second group of ventilating holes of the four caniage panels, and a ventilating space provided by forming a space between the internal housing and the external housing in order to facilitates the flow of the air.

[106] On the other hand, a cable connection system, in which four individual cable connection structures connected to four hard discs are provided (1 : 1 storage apparatus - host connection structure), and four hard discs can be connected to a host by one integrated cable as well, provides an environment that a user can connect a storage apparatus to a PC very conveniently and diversely. Approaching from the viewpoint of a PCI controller, a publicized S-ATA PCI controller distributed on the market has an interface connecting one S-ATA cable to each S-ATA channel (one S-ATA hard disc) consistently, so that, when a storage apparatus is used after installing such a PCI controller, one cable for each hard disc, four S-ATA cables in total, is used. In this case, first, several cables are connected, so that the appearance is not smart, second, an S-ATA cable is easily broken due to the connector structure, third, conventional PCI controllers provides only two S-ATA interfaces on the bracket, so that the interface cannot be added due to the length limit of the bracket of a PCI card, therefore, in order to connect four hard discs, the cable must be inserted inside a PC. However, if a PCI controller developed for the present invention is used, those problems can be solved at a stroke. That is, an S-ATA PCI controller of the invention can connect hard discs in the same way as a conventional PCI controller, and, furthermore, four hard discs can be connected by one cable through another interface called as an integrated cable connector. Also, the fact that only two interfaces are exposed outside, a problem of a conventional PCI controller, can be solved such that four external interfaces can be provided by adding an extra bracket.

[107] On the other hand, the storage apparatus of the invention has no limitation in loading capacity. However, S-ATA hard discs of 400GB capacity are on the market presently, therefore, when four hard discs are mounted on the storage apparatus of the invention, a maximum of 1.6TB storage capacity can be constructed. The purpose of describing an embodiment of four hard discs is to provide a user with a storage apparatus of lower cost in the low-end storage market.

[108] While the present invention has been described with reference to the particular illustrative embodiments, it is not to be restricted by the embodiments but only by the appended claims. It is to be appreciated that those skilled in the art can change or modify the embodiments without departing from the scope and spirit of the present invention.

[109]

Claims

[1] A serial ATA type external storage apparatus communicating with a host using a serial ATA, the external storage apparatus comprising: a storage housing wherein an external housing, an internal housing, a rear panel, and a front cover are assembled in one set; a plurality of hard disc carriage panels which receive and firmly attach hard discs, and carry and insert the hard discs into the housing; a host connector receiver which includes a single connector receiver, corresponding in one-to-one manner, to each inserted hard disc independently and an integrated connector receiver which connects embedded hard discs, which are integrated into one connector through a data bridge between the hard discs, to one host cable; a serial ATA main-board inserted into the rear portion of the inside of the housing, which is electrically connected to the hard discs received by the carriage panel inserted inside the housing and communicates with the host through the single connector receiver and the integrated connector receiver; a cooling fan which is configured to cool down the temperature of the inside of the housing which goes up due to the operation of hard discs; and an external DC adapter which supplies driving power to the internal devices inside the housing, including the serial ATA main-board.

[2] The external storage apparatus according to claim 1, wherein a first group of ventilating holes is formed on at the front portion of both sides of the external housing.

[3] The external storage apparatus according to claim 1, wherein the structure of the internal housing comprises: a top surface which is LI in width and L2 in length; a left surface connected to the front cover connector which is protruded by d3 toward the front, wherein the rear portion is extended by dl toward the rear of the housing, bent 90 degrees toward the external housing, and extended by d2, and the front portion is bent 90 degrees toward the external housing without extension of dl and extended by d2; and a right surface which is formed of a structure symmetrical to the left surface, and secures ventilating space so that the air inside the housing may flow back and forth, and left and right, and communicates with the ventilating hole group of the external housing.

[4] The external storage apparatus according to claim 3, wherein the internal housing includes multiple guide rail grooves which guide the carriage panels into the internal housing, and multiple carriage panel supports which firmly support each carriage panel to the conesponding layer.

[5] The external storage apparatus according to claim 1, wherein the carriage panel comprises: a hard disc receiver; hard disc side supports which extend upwardly from both sides of the hard disc receiver with them being bent 90 degrees and support the sides of a hard disc; a hard disc connector which fixedly attaches a hard disc to a carriage panel; and a connector which connects the carriage panel to the housing by connector means, wherein the hard disc receiver has a second group of ventilating holes formed thereon so as to exhaust the flow of the heat generated by the hard discs.

[6] The external storage apparatus according to claim 1, further comprising a display means which displays the operation status of the embedded hard discs and the power status.

[7] The external storage apparatus according to claim 1 or 3, wherein the internal housing is configured so as to include four layers, provide four carriage panels, and mount four hard discs.

[8] The external storage apparatus according to claim 1 or 3, wherein the cooling fan is a dual fan structure comprising two cooling fans which adopt the ball bearing method.

[9] A serial ATA type external storage apparatus communicating with a host using a serial ATA, which comprises a serial ATA main-board electrically connected to a single connector for connecting a hard disc to a host in one-to-one manner and an integrated connector for connecting hard discs to a host in N-to-one manner (N is an integer greater than one, the number of mounted hard discs), secures ventilating space by defining a certain gap between the internal housing and the external housing, allows a first group of ventilating holes to be formed at the front portion of both sides of the external housing, allows a second group of ventilating holes to be formed on the carriage panel for carrying the hard disc into the internal housing, and cools down the temperature of the inside of the housing by two cooling fans.

[10] The external storage apparatus according to claim 1 or 9, wherein the external storage apparatus further comprises a switching means which selects one of the single connector and the integrated connector, and, the operation of the switching means enables the integrated connector to be switched off when the single connector is used, and the single connector to be switched off when the integrated connector is used, thereby preventing the data interference between the single connector and the integrated connector.