Abstract: A control device managing a plurality of nodes transmitting and receiving data containing an error correcting code, comprises means accepting, when any one of the nodes detects an uncorrectable error from the data containing the error correcting code, a signal transmitted by the node detecting the error, means judging from a record of the detection of a first node, when accepting the signal from a second node receiving data transmitted by the first node, whether or not the first node has detected the uncorrectable error from the data transmitted to the second node, and means stopping, when the first node has detected the uncorrectable error from the data transmitted to the second node, a process attributed to the acceptance of the signal from the second node.

Abstract: A request issued by the CPU is output from the local arbiter by way of the CPU bus and the CPU-issued request queue. The cache replacement request loop-back circuit determines at the loop-back determination circuit whether the outputted request is a cache replacement request or not. A request other than a cache replacement request is output onto the local bus. A cache replacement request is output to the selector and sent to the request handling section when there is no valid request on the global bus.

Abstract: In a system controller including a CPU-issued request queue having a circuit that processes plural requests having identical addresses not to be inputted to the CPU-issued request queue, a latest request other than a cache replace request is retained by an input-request retaining section. Consequently, even if an address of an issued request for cache replace request matches an address of a request retained by the CPU-issued request queue, the issued request for the cache replace request is not retried but is queued in the CPU-issued request queue when the address of the issued request for the cache replace request does not match the entire address retained by the input-request retaining section.

Abstract: In a multiprocessor system, a system controller includes snoop tags which are copy information on cache tags retained by respective CPUs. If the same address is registered in S (Shared state) in the cache tag of each of the CPUs connected to the same CPU bus, the address is registered in S (Shared state) in only any one of the snoop tags corresponding to the CPUs in which the same address is registered.

Abstract: A hydrodynamic bearing rotary device which can reduce rotation friction, and recording and reproducing apparatus including the same are provided. In the hydrodynamic bearing rotary device such as hard disc devices, a rotary shaft having a hub on one end is provided in a bearing of a sleeve so as to be rotatable. Thrust hydrodynamic grooves are provided on the other end surface of the rotary shaft, to form a thrust bearing with the thrust plate. A communication path is provided in the sleeve. The second gap between the hub and the sleeve end surface is used as a flow channel and is connected to the communication path. In this way, the rotation friction torque of the thrust bearing can be made sufficiently small, and internal pressure in bonded portions of the rotary shaft or the bottom plate can be suppressed. Thus, the oil can be prevented from oozing out from a small space of the bonded surfaces. Furthermore, the hydrodynamic bearing can be made thin.

Abstract: An object of the present invention is to provide a hydrodynamic bearing type rotary device which can improve rotation performance, suppress a friction torque, and reduce power consumption of motor, and a recording and reproducing apparatus including the same. A shaft having a flange on one end and a hub on the other end is provided with a bearing of a sleeve so as to be rotatable. The sleeve includes a communication hole. A third gap between the hub and the sleeve end surface is a flow path, and is connected to the communication hole. Provided that a first gap between a thrust plate 4 and the flange 3 is S1, a second gap between the flange 3 and a lower end surface of the sleeve 1 is S2, and a third gap between the upper end surface of the sleeve 1 and the hub 7 is S3, widths of the gaps satisfy the relational expression, S3>(S1+S2).

Abstract: A high-accuracy, long-life hydrodynamic bearing that does not cause oil film breakage in bearing clearances and a disc rotation apparatus using the bearing is disclosed. Oil film breakage is avoided as negative pressure is prevented from generating between the shaft and sleeve of the hydrodynamic bearing. Herringbone shaped dynamic pressure generating grooves, located on the thrust bearing section and the radial bearing section of the hydrodynamic bearing, are oil filled and have optimum shapes. The optimum shapes prevent the generation negative pressure and thus prevents the coagulation of air bubbles that can cause oil film breakage. The disc rotation apparatus, that holds a reproduction/recording disc, is concentrically secured to the hydrodynamic bearing and rotated. The disc is put into contact with magnetic or optical heads while rotating in the disc rotation apparatus. Both the hydrodynamic bearing and the disc rotation apparatus experience high reliability.

Abstract: A high-accuracy, long-life hydrodynamic bearing that does not cause oil film breakage in bearing clearances and a disc rotation apparatus using the bearing is disclosed. Oil film breakage is avoided as negative pressure is prevented from generating between the shaft and sleeve of the hydrodynamic bearing. Herringbone shaped dynamic pressure generating grooves, located on the thrust bearing section and the radial bearing section of the hydrodynamic bearing, are oil filled and have optimum shapes. The optimum shapes prevent the generation negative pressure and thus prevents the coagulation of air bubbles that can cause oil film breakage. The disc rotation apparatus, that holds a reproduction/recording disc, is concentrically secured to the hydrodynamic bearing and rotated. The disc is put into contact with magnetic or optical heads while rotating in the disc rotation apparatus. Both the hydrodynamic bearing and the disc rotation apparatus experience high reliability.

Abstract: Radial dynamic pressure grooves are provided in a first region 4A and a second region 4B on the side of a fixed shaft 2. A vent 2D is provided inside the top end 2A of the fixed shaft 2. The vent 2D connects spaces over and under a flange 3 to each other. The flange 3 in an annular shape is fixed at the top end 2A of the fixed shaft 2. Thrust dynamic pressure grooves 3A and 3B are provided on the surfaces of the flange 3. A circulation hole 3C is provided in the flange 3, and connects spaces over and under the flange 3 to each other. A sleeve 4 revolves around the fixed shaft 2. A thrust plate 6 in an annular shape is fixed at the top of the sleeve 4 and opposed to the flange 3. The first region 4A, the second region 4B, the thrust dynamic pressure grooves 3A and 3B, and the circulation hole 3C of the flange 3 are filled with a lubricant 7.

Abstract: An information processing device of a multiprocessor configuration that can increase significantly the processing capability of read requests. The information processing device comprises a plurality of processing units, a plurality of cache memories for storing temporarily the data read by the plurality of processing units from respective main memories in combination with tag information indicating the state of the data that will be stored, and a system controller for controlling the access of the plurality of processing units to the main memories. The system controller comprises a tag copy unit for holding a copy of the tag information that will be stored in the cache memory, a plurality of write cues for storing write requests, and a store buffer for storing the arbitration results relating to a plurality of write requests that will be stored in the plurality of write cues.

Abstract: A sleeve 1 is fixed on a base. Radial dynamic-pressure generating grooves 1A and 1B are provided on an inner surface of the sleeve 1. A thrust plate 4 hermetically seals a lower opening end of the sleeve 1. A shaft 2 is inserted inside the sleeve 1, being allowed to revolve. A flange 3 is fixed at the bottom end of the shaft 2, and its lower surface is placed close to an upper surface of the thrust plate 4. Thrust dynamic-pressure generating grooves 3A and 3B are provided on the surfaces of the flange 3. Gaps A–H among the sleeve 1, the shaft 2, the flange 3, and the thrust plate 4 are filled with a lubricant 5. Hollows 1C–1F are provided on the inner surface of the sleeve 1. The gaps A and C over the thrust dynamic-pressure generating grooves 3A and 3B and their vicinities are narrower than the surrounding gaps B and D (A<B, A<D, C<B, and C<D), and the surrounding gaps B and D are narrower than the gap H in the upper opening end of the sleeve 1 and its vicinity (B<H and D<H).

Abstract: A fluid dynamic bearing device including a shaft having an interior pressure regulating hole by which a center portion of a thrust surface confronting a thrust plate and a lubricant pool portion of an inner circumferential surface of a sleeve are communicated with each other. Thus, the device is capable of obtaining stable thrust floating characteristics and preventing leaks of the lubricant as well as exhaustion of the lubricant.

Abstract: The present invention is aimed at solving a problem that a non-uniform luminance and white uneveness which may be caused by contact between a reflecting sheet and a protecting member. A light source side end portion (3a) of a reflecting sheet (3) and a protecting member (5) are located with a spacing (H) between them for preventing contact between them. The spacing (H) for preventing contact between them may be obtained by decreasing a protruding length of the light source side end portion (3a) of the reflecting sheet (3), by displacing a light source (2), or by decreasing diameters of the light source (2) and the protecting member (5).

Abstract: In order to provide a high-accuracy long-life hydrodynamic bearing not causing oil film breakage in bearing clearances and a disc rotation apparatus using the bearing, when the outside diameter of the herringbone pattern of dynamic pressure generation grooves provided on at least one of the opposed faces of a flange and a thrust plate is designated as dlo, the inside diameter thereof is designated as dli and the diameter of the turn-back part thereof is designated as dlm, the diameter dlm of the turn-back part is set so as to satisfy the relationships represented by the following equations:

Abstract: Radial dynamic pressure grooves are provided in a first region 4A and a second region 4B on the side of a fixed shaft 2. A vent 2D is provided inside the top end 2A of the fixed shaft 2. The vent 2D connects spaces over and under a flange 3 to each other. The flange 3 in an annular shape is fixed at the top end 2A of the fixed shaft 2. Thrust dynamic pressure grooves 3A and 3B are provided on the surfaces of the flange 3. A circulation hole 3C is provided in the flange 3, and connects spaces over and under the flange 3 to each other. A sleeve 4 revolves around the fixed shaft 2. A thrust plate 6 in an annular shape is fixed at the top of the sleeve 4 and opposed to the flange 3. The first region 4A, the second region 4B, the thrust dynamic pressure grooves 3A and 3B, and the circulation hole 3C of the flange 3 are filled with a lubricant 7.

Abstract: A sleeve 1 is fixed on a base. Radial dynamic-pressure generating grooves 1A and 1B are provided on an inner surface of the sleeve 1. A thrust plate 4 hermetically seals a lower opening end of the sleeve 1. A shaft 2 is inserted inside the sleeve 1, being allowed to revolve. A flange 3 is fixed at the bottom end of the shaft 2, and its lower surface is placed close to an upper surface of the thrust plate 4. Thrust dynamic-pressure generating grooves 3A and 3B are provided on the surfaces of the flange 3. Gaps A-H among the sleeve 1, the shaft 2, the flange 3, and the thrust plate 4 are filled with a lubricant 5. Hollows 1C-1F are provided on the inner surface of the sleeve 1. The gaps A and C over the thrust dynamic-pressure generating grooves 3A and 3B and their vicinities are narrower than the surrounding gaps B and D (A<B, A<D, C<B, and C<D), and the surrounding gaps B and D are narrower than the gap H in the upper opening end of the sleeve 1 and its vicinity (B<H and D<H).

Abstract: A pressure regulating hole by which a center portion of a thrust surface confronting a thrust plate and a lubricant pool portion of an inner circumferential surface of a sleeve are communicated with each other is provided inside the shaft in a fluid dynamic bearing device. Thus, the device is capable of obtaining stable thrust floating characteristics and preventing leaks of the lubricant as well as exhaustion of the lubricant.

Abstract: In order to provide a high-accuracy long-life hydrodynamic bearing not causing oil film breakage in bearing clearances and a disc rotation apparatus using the bearing, when the outside diameter of the herringbone pattern of dynamic pressure generation grooves provided on at least one of the opposed faces of a flange and a thrust plate is designated as d1o, the inside diameter thereof is designated as d1i and the diameter of the turn-back part thereof is designated as d1m, the diameter d1m is selected so that the difference between the diameters dsy and d1m becomes 0.05 mm or more and 0.

Abstract: A memory control device includes a writing unit writing information to a memory module, a reading unit reading the information from the memory module, an error detecting unit executing a detection of an error in the formation in parallel with the reading operation by the reading unit, an error correcting unit correcting the error in the information containing the error detected, and a control unit controlling a transfer and a receipt of the information to and from an external device and stopping, when the error is detected, an output of the information to the external device.

Abstract: A vacuum pump includes a positive displacement vacuum pump structure section disposed on a discharge opening side; a kinetic vacuum pump structure section, disposed on a suction opening side, for providing a high vacuum; and a kinetic vacuum pump structure section, disposed on a suction opening side, for providing a high pumping speed. The construction of the kinetic vacuum pump structure section is different from that of the kinetic vacuum pump structure section so as to differ relative thereto in one of ultimate pressure, pumping speed, and pumping speed of sucked gas with respect to a molecular weight of the sucked gas.