摘要:
The present invention is directed to utilizing the capabilities of multi-stage actuators in disk drives to write servo tracks that have a variable number of tracks-per-inch (TPI) from head to head, thereby improving both the performance of the drive and manufacturing yields. An appropriate TPI for a particular head has been found to depend on a number of factors that vary from head to head. Consequently, the initial step is to determine an appropriate TPI for at least one of the heads or, more preferably, all of the heads in the drive. The determination typically involves measurements such as read and write width measurements and off-track performance tests for the relevant heads. Once an appropriate TPI format has been determined, the servo tracks are written according to the TPI formats using either a servo track writer or self servo track writing.
摘要:
The present invention is directed to utilizing the capabilities of multi-stage actuators in disk drives to do self servo writing on the disk surfaces, thereby avoiding the use of a servo track writer. In one embodiment, a crash stop that limits the range of motion of a primary actuator is used as an initial reference point for a secondary actuator associated with a first head to position the first head to write a first servo track on a first disk surface. The first servo track is subsequently used as a reference point for a secondary actuator associated with a second head to position the second head for writing one or more servo tracks on a second disk surface. One of these servo tracks on the second disk surface is then used as the reference point relative to which the primary and/or secondary actuator associated with the first head moves the first head to write one or more servo tracks on the first disk surface. This process of alternatingly using the servo tracks written by one head as the reference point relative to which the primary and/or secondary actuators move the other head to write further servo tracks is repeated until all of the desired servo tracks are written.
摘要:
The present invention is directed to a disk drive that utilizes a multi-stage actuator associated with two or more heads that are each associated with a separate disk surface to realize high speed data transfers. In one embodiment, the multi-stage actuator is used to simultaneously transfer portions of a data file between the heads and the associated disk surfaces and to perform simultaneous seek operations for the heads between data transfer operations. In another embodiment, the multi-stage actuator is used to alternatingly transfer portions of a data file between the heads and the associated disk surfaces and to perform alternating seek operations for the heads such that one head is transferring data while another head is performing a seek operation.
摘要:
A system employing vector signal generator (VSG) and vector signal analyzer (VSA) modules or cards that are configured to test multiple devices under test simultaneously. Each VSG is configured to generate multiple RF test signals and send them to multiple devices under test simultaneously. Similarly, each VSA is configured with multiple signal receiving modules connected to a single controller or memory. Each signal receiving module receives an RF signal from a device under test, converts it to a baseband digital signal, and transmits this digital signal to the VSA's memory. A single RF testing system can employ multiple such VSGs and VSAs, each capable of evaluating multiple devices under test. Each VSG/VSA can further be tuned for operation in discrete or defined frequency bands, which are narrower than those for conventional RF testers, and which can correspond to various wireless standards.
摘要:
The present invention relates to aralkyl piperidine derivatives, compositions containing the same, and their uses in the preparation of antalgic or ataractic medicament. The said derivatives are a free base of the compound represented by the following formula or a salt thereof. The pharmacological experiments show that they display favorable antalgic, ataractic activity and low side effects.
摘要:
A thin film piezoelectric element includes a piezoelectric thin film layer, a seed layer and an elastic substrate layer. The piezoelectric thin film layer is a laminated structure comprising a first electrode layer, a second electrode layer and a piezoelectric layer sandwiched between the first electrode layer and the second electrode layer. The seed layer is formed on the second electrode layer, and the elastic substrate layer is formed on the seed layer. The thin film piezoelectric element is a single layer structure and has an elastic substrate layer for supporting the single layer structure, thereby it has enough stiffness and flexibility to afford facilities for manufacture and assembly and to avoid film peeling and deformation, ultimately increasing the production efficiency and lowering the cost. The invention also discloses a method for manufacturing the thin film piezoelectric element, a head gimal assembly and a disk drive unit with the same.
摘要:
The use of aryl piperazines of formula (I) in manufacturing a medicament for treating acute pain, neuropathic pain or receptive nociceptive pain in mammals including human beings is disclosed.
摘要:
A suspension for a HGA includes a suspension flexure and an out trigger. The suspension flexure has a tongue region having a first flexure part in a tip portion thereof for mounting a trailing edge of a slider and a PZT mounting region for mounting PZT elements. One end of the out trigger is connected to the suspension flexure, and the other end of the out trigger has a trigger support portion which extends above the tongue region so as to support the leading edge of the slider. The structure of the out trigger is capable of stiffening the tongue region of the suspension flexure and, in turns, avoiding the deformation problem and the dimple separation problem during the manufacturing process or in vibration or shock events. The invention also discloses a HGA with the suspension, manufacturing methods of the HGA and a disk drive unit having such HGA.
摘要:
A disk drive detects head touchdown based on a magnitude of a position error signal at a discrete frequency. The discrete frequency is one-half the disk rotation frequency or an integral multiple of the disk rotation frequency. The head is heated by turning on a heater at the discrete frequency, thereby injecting bias into a servo system that increases the PES magnitude. In addition, the servo system has a first transfer function for tracking the head during read and write operations and a second transfer function for tracking the head during head touchdown detection. The second transfer function has smaller vibration rejection than the first transfer function so that the disk drive is less sensitive to vibration during read and write operations than during head touchdown detection.
摘要:
Track pitch for writing tracks on a disk is determined based on an available stroke across the disk. The available stroke is identified by searching across the disk for where information can be written and read. The track pitch is determined for writing tracks on the disk based on the available stroke across the disk. Tracks are written on the disk based on the determined track pitch.