Abstract: A ring network system is a ring network system in which a plurality of nodes including a blocking node that blocks transfer of a predetermined frame are connected in a ring shape, and when, any one of the plurality of nodes detects a change in a link state with an adjacent node, the node detecting the change transmits a collision frame for inquiring a collision of a blocking node to a current blocking node, and in accordance with a response from the current blocking node, a determination is made which of the nodes is to be a new blocking node, and in a case where the link state with the adjacent node has a higher priority level of blocking than a link state between the current blocking nodes, the node having detected the change transmits a collision frame for inquiring a collision of the blocking node.

Abstract: A machine tool includes a clamping mechanism for clamping/unclamping rotation of a rotary table. A load is measured when an unclamping command is output and then the rotary table is rotated after a set time set in the timer passes, and the set time of the timer is changed in response to a magnitude of the measured load. In this way, it is possible to prevent the clamping mechanism from being damaged due to a subsequent command given before unclamping ends, and extend a life span of a component.

Abstract: A rotary table includes a clamping mechanism including a piston driven by operating fluid in a direction of either of clamping and unclamping a brake disc, and a biasing means fixed by a case and the piston to always bias the piston in a direction of either of clamping and unclamping the brake disc by a recovery force of elastic deformation.

Abstract: A unidirectional relay device includes a first port that receives communication data from one network, a first physical layer circuit that performs a protocol process of a physical layer, a first MAC layer circuit that performs a protocol process of a MAC layer, a second MAC layer circuit that is connected to the first MAC layer circuit through a signal line to perform a protocol process of a MAC layer, a second physical layer circuit that performs a protocol process of a physical layer, and a second port that transmits communication data to the other network. The signal line is a signal line that transmits data unidirectionally to the second MAC layer circuit from the first MAC layer circuit, and a signal line for transmitting data from the second MAC layer circuit to the first MAC layer circuit is opened or is connected to a ground.

Abstract: A machine tool includes a clamping mechanism for clamping/unclamping rotation of a rotary table. A load is measured when an unclamping command is output and then the rotary table is rotated after a set time set in the timer passes, and the set time of the timer is changed in response to a magnitude of the measured load. In this way, it is possible to prevent the clamping mechanism from being damaged due to a subsequent command given before unclamping ends, and extend a life span of a component.

Abstract: A rotation table mounted on a machining table of a machine tool includes a clamping mechanism which is driven by air so as to clamp a rotation shaft, and an air purging pressure is applied into a casing so as to prevent a cutting fluid or foreign matter from intruding into the casing of the rotation table. Then, air discharged from the clamping mechanism does not pass through the casing, to which the air purging pressure is applied, and is discharged to the outside of the rotation table through a flow passage.

Abstract: Disclosed is a storage device using non-volatile semiconductor memory that achieves high performance and long life for the device. When managing the non-volatile semiconductor memory (2), physical blocks are classified into three types: scratch blocks (22), data blocks (23), and erased blocks (24). Data writing from a host device (3) is performed on the scratch blocks. When the number of empty pages within a scratch block becomes less than a predetermined number or no longer exists, the block is treated thereafter as a data block, and one of the erased blocks is newly assigned as a scratch block. If there are insufficient erased blocks, a block with relatively less valid data is selected from among the data blocks. After copying all valid data included in the block to a scratch block, the block is erased, and thus an erased block is acquired.

Abstract: A machine tool includes a shaft load measuring unit measures a load of the main shaft motor. When a measured load of the main shaft motor exceeds a predetermined value, it is determined that a tool is brought into contact with a work. Detection and correction of thermal displacement of the main shaft are performed by comparing a reference time and a measured time for the tool to reach the work.

Abstract: A storage device includes a non-volatile memory, a cache memory and a memory controller. The non-volatile memory stores a logical-to-physical address translation table for managing partitioned data and storage locations thereof. The cache memory stores a data cache and a logical-to-physical address translation table cache which holds a portion of the logical-to-physical address translation table. When the memory controller receives a data read-out request from outside, in the case no empty entry is found in the data cache, among the partitioned data in the data cache, it creates an empty entry to read out the data thereto by evacuating partitioned data of which entries in the logical-to-physical address translation table exist in the logical-to-physical address translation table cache into the non-volatile memory prior to other partitioned data.

Abstract: Disclosed is a storage device using non-volatile semiconductor memory that achieves high performance and long life for the device. When managing the non-volatile semiconductor memory (2), physical blocks are classified into three types: scratch blocks (22), data blocks (23), and erased blocks (24). Data writing from a host device (3) is performed on the scratch blocks. When the number of empty pages within a scratch block becomes less than a predetermined number or no longer exists, the block is treated thereafter as a data block, and one of the erased blocks is newly assigned as a scratch block. If there are insufficient erased blocks, a block with relatively less valid data is selected from among the data blocks. After copying all valid data included in the block to a scratch block, the block is erased, and thus an erased block is acquired.

Abstract: A nonvolatile memory stores therein a plurality of partitioned translation tables which are created by partitioning a logical-to-physical address translation table in a page unit. A RAM stores therein a logical-to-physical address translation table cache for storing at least the one or more partitioned translation tables, a translation-table management table for managing the partitioned translation tables, and a cache management table for managing the logical-to-physical address translation table cache. The translation-table management table includes a cache presence-or-absence flag and a cache entry number, the cache presence-or-absence flag being used for indicating that the partitioned translation tables are stored into the logical-to-physical address translation table cache, the cache entry number being used for indicating storage destinations of the partitioned translation tables in the logical-to-physical address translation table cache.

Abstract: A fluid pressure control valve apparatus for a clutch or a brake which is small in size and capable of reducing occurrence of malfunction of a pressure control valve caused by dust caught therein is provided. For this purpose, a fluid pressure control valve apparatus (2) for controlling a pressure of a fluid and feeding it to a clutch or a brake includes a pressure control valve (30) for controlling fluid pressure, an electromagnetic proportional pilot operated valve (50) for issuing an operation command for the pressure control valve with pilot pressure according to a command current to a proportional solenoid (40), and a flow detecting valve (10) for detecting a flow of the fluid to be fed to the clutch or the brake from the pressure control valve to detect completion of filling in the clutch or the brake.

Abstract: A fluid pressure control valve apparatus for a clutch or a brake which is small in size and capable of reducing occurrence of malfunction of a pressure control valve caused by dust caught therein is provided. For this purpose, a fluid pressure control valve apparatus (2) for controlling a pressure of a fluid and feeding it to a clutch or a brake includes a pressure control valve (30) for controlling fluid pressure, an electromagnetic proportional pilot operated valve (50) for issuing an operation command for the pressure control valve with pilot pressure according to a command current to a proportional solenoid (40), and a flow detecting valve (10) for detecting a flow of the fluid to be fed to the clutch or the brake from the pressure control valve to detect completion of filling in the clutch or the brake.