Hitachi, Ltd.

Hitachi Global Storage Technologies Japan, Ltd.

Hayato Shimizu

Mikio Tokuyama

Shozo Saegusa

Yuzo Yamaguchi

Masahiko Sega

Toshihisa Okazaki

Satomitsu Imai

Shigeo Nakamura

Shigenori Togashi

Kazuo Sakai

Masao Iwakura

Toshiaki Kobari

Masayuki Kaiho

Toshihiko Shimizu

Yoshihiro Shiroishi

Masaaki Matsumoto

Norio Nakazato

Takashi Kouno

Eiji Ishii

Jun Okitsu

Kiyokazu Saigo

Kentaro Sano

An air conditioning system having an inlet air temperature calculating block that calculates a variation in air temperature at an inlet port of each unit based on position information and also calculate the air flow rate through each unit. A temperature sensitivity calculating block calculates temperature sensitivity of each unit obtained by dividing the variation in air temperature at the inlet port by a variation in air temperature at an outlet port of each unit. An inlet air temperature calculating block calculates the air temperature at the inlet port of each unit on the basis of the air temperature at the outlet port of each unit, and the temperature sensitivity.

Air-conditioning control apparatus for data center

A measuring device of air flow rate for an air conditioning system which accurately measures the flow rate of cooling air blowing out of the openings of some rectangular units and in which the locations of the openings can be changed according to the location of equipment. The measuring system includes a plurality of panels constituting a floor surface, ceiling surface, or wall surface, a rectangular vent unit with openings located in place of a given one of the panels, a space with a given height formed by pillars on the back sides of the rectangular vent unit and the panels, and an air conditioner for supplying cooking air to the space. The cooling air from the space passes through the openings. A measuring means for measuring the flow rate of cooling air passing through the openings is located in a rib which forms the openings.

Measuring device of air flow rate for air conditioning system

There are a large number of operation workload reallocating plans, but in terms of a required calculation resource, it is undesirable to, in each case, derive power consumption required for a cooling apparatus, select and control operation workload deployment for minimizing a total value of the derived power consumption and server power. The present invention derives a rule about the IT workload allocation in advance from configuration information (static information) including position information of facilities including an air conditioner of the data center and the IT equipment items, changes priority of an applied rule on the basis of dynamic information including ambient temperature, and changes the IT workload allocation, thereby reducing the power consumption of the air conditioner.

Management computer, computer system including the same, and method for providing allocating plan for it equipment

A magnetic disc unit includes a rotating disc type magnetic disc, a head for recording and reproducing data to and from the magnetic disc, and a head support mechanism for supporting the head. The magnetic disc unit includes a shroud surrounding an outer periphery of the magnetic disc other than at least at an inserting part of a carriage arm which is linked to the magnetic head support mechanism. A gap between an end face of the outer periphery of the magnetic disc and the shroud is set in a range not less than 0.1 mm but not greater than 0.4 mm.

Magnetic disc unit with gap between magnetic disc and shroud

A magnetic disc unit includes a rotating disc type magnetic disc having an outer periphery, and a carriage arm linked to a head support mechanism for a recording/reproducing head. A base has an outer periphery and mounts the rotating disc type magnetic disc and the carriage arm, and has a side wall with an inner wall surface having an opening for inserting the carriage arm. The inner wall surface of the side wall defines a shroud surrounding the outer periphery of the magnetic disc, except at the opening in the side wall where the shroud is projected inwardly so as to decrease an opening angle of the opening in the side wall. A gap between the outer periphery of the magnetic disc and the shroud is set in a range not less than 0.1 mm but not greater than 0.6 mm.

A magnetic disk apparatus includes a plurality of magnetic disks driven to rotate by a spindle motor, arms supporting magnetic heads on the magnetic disks, an actuator for moving the arms on the magnetic disks by a voice coil motor, and a housing which surrounds the magnetic disks, the arms and the actuator. A shroud which arcuately surrounds the magnetic disks along the outer periphery thereof has an opened portion for inserting the arms is formed in a part of the housing. The shroud on an upstream side of the arms relative to airflow generated by the magnetic disks when rotating is provided with an opening having a greater width than that of a gap defined between the shroud and the outer periphery of the magnetic disks. An empty bypass channel is provided which communicates from the opening through a rear side of the voice coil motor to the downstream side of the arms.

Magnetic disk apparatus with shroud and having open space downstream of moveable arms in communication with bypass channel

A magnetic disc unit having a rotating disc type magnetic disc, a head for recording and reproducing data to and from the magnetic disc, and a shroud surrounding an end surface of an outer periphery of the magnetic disc, except a part where a carriage arm is inserted, wherein a gap between the outer peripheral end surface of the magnetic disc and the shroud is set in a range which is greater than 0.1 mm but not greater than 0.6 mm.

Magnetic disc unit with range of gap between disc and shroud

A magnetic disk apparatus includes magnetic disks stacked on a rotating shaft, arms supporting magnetic heads, a rotary actuator for moving the arms, and a housing forming at least a part of an arcuate-shaped shroud which substantially surrounds a portion of side surfaces of the magnetic disks so as to define a gap between the shroud and the portion of the side surfaces of the magnetic disks. The arcuate-shaped shroud has portions delimiting an open space adjacent to another portion of the side surfaces of the magnetic disks which is located on a downstream side of the arms relative to an air flow which moves on surfaces of the magnetic disks. A bypass channel provides air flow to the disks in a region of the open space at a reduced pressure on the downstream side of the arms with respect to pressure at an upstream side of the arms.

Magnetic disk apparatus with air flow bypass channel

A magnetic disc unit which can restrain occurrence of flutter so as to countermeasure such a problem that the larger the rotational speed of discs, the higher the flutter, causing heat positioning errors, in order that the high rotational speed and high positioning accuracy are consistent with each other. Discs are surrounded along their outer peripheries by a shroud (outer wall) while a gap between end faces of the discs and the shroud is decreased to a predetermined distance, thereby to eliminate air pressure differential between opposite surfaces of each of the discs in order to reduce flutter.

Magnetic disc unit

The structure is made such that an aerodynamic latch is provided in an outer portion of a magnetic disc, a front end portion exposed to a wind in the aerodynamic latch is formed to be shorter than an outer peripheral surface of the magnetic disc, and the wind receiving portion of the aerodynamic latch moves an air stream outlet from an end surface of the magnetic disc and a shroud in a direction of forming a flow passage for passing through a portion apart from the magnetic disc. Accordingly, a stable aerodynamic latch drive can be achieved and an air stream within the disc is not disturbed, so that it is possible to reduce a flutter and a consumed electric power.

Magnetic disc arrangements with aerodynamic latch mechanism

In a magnetic disc apparatus including a plurality of magnetic discs mounted on a spindle, arms supporting magnetic heads, a rotary actuator for the arms, and a housing having an arcuate-shaped shroud, the improvement wherein gaps between the shroud and the sides of outer peripheries of the magnetic discs are larger than 0.1 mm and less than 0.6 mm. An open space is located, downstream of the arms with respect to the air flow on surfaces of the magnetic discs, the open space being devoid of the shroud. An opening is provided in the shroud, upstream of the arms with respect to the air flow and having a greater width than a width of the gaps defined between the magnetic discs and the shroud, and a bypass channel is provided which communicates between the opening and open space.

Magnetic-disc unit with gap between disc and shroud

A magnetic head supporting apparatus having a magnetic head for reading and writing information on a magnetic disc, a slider for mounting the magnetic head, and a suspension for supporting the slider. An IC chip for controlling a signal of the magnetic head is mounted on a heat insulating substrate which substantially prevents conduction of heat therethough, and the heat insulating substrate is mounted to the suspension.

Magnetic head supporting apparatus having thermally insulated IC mounted on an arm portion

A magnetic disk apparatus arranged in a housing having a plurality of magnetic disks stacked on a rotating shaft, arms supporting thereon magnetic heads and adapted to be inserted between said magnetic disks, a rotary actuator for moving the arms, a housing forming at least a part of an arcuate-shaped shroud which substantially surrounds a portion of side surfaces of the magnetic disks so as to permit movement of the arms and which is concentric with the magnetic disks so as to define a gap between the shroud and the portion of the side surfaces of said magnetic disks. The gap defined between the outer peripheral end surfaces of the magnetic disks and the shroud is in a range of 0.1 mm to 0.6 mm.

Magnetic disk apparatus

A magnetic head supporting apparatus includes a magnetic head for reading and writing information on a magnetic disc, a slider having the magnetic head, and a suspension for supporting the slider. An IC chip for controlling a signal of the magnetic head is mounted on a first surface of a heat insulating substrate, and a second surface of the heat insulating substrate opposite to the first surface thereof is mounted to the suspension.

Magnetic head supporting apparatus having thermally insulated read/write IC mounted on arm portions thereof

To suppress pressure fluctuation caused by insertion of arms between disks, which arms support thereon magnetic heads, to reduce disk flutter to thereby reduce disk driving power in a magnetic disk apparatus, there are provided an open space not covered by a shroud, which constitutes a part of a housing structure to cover a side surface of a disk stack, and provided on a downstream side of the arms relative to an airflow moving along surfaces of the disks as the disks rotate, and a channel, which connects a space on an upstream side of the arms and the open space not restricted by the shroud on the downstream side of the arms, the channel being provided with a linear section, which has a rectifying effect on the airflow.

Growing community of inventors

Ryugasaki, Japan

Hayato Shimizu