The earliest hard drive was called "Winchester hard drive"! In 1973, IBM successfully developed a hard disk IBM 3340 that was put into practical use. IBM calls it a Winchester hard drive. Mechanical hard disk is our traditional Winchester hard disk, we usually call it "hard disk". Due to the long application time and extensive coverage, it has now been applied to various fields on a large scale, but its structure is complex. With the continuous improvement of technology, the distance between the magnetic head and the magnetic sheet is getting smaller and smaller, and weak vibration during work may cause Damage to the hard disk When a file needs to be read from the hard disk, the head will first be required to locate the starting sector of the file. This positioning process consists of two steps: Position the magnetic head to the corresponding track; The spindle motor drives the platters to rotate to the correct position. The time spent in this process is called address time. In other words, the addressing time actually consists of two parts: The time when the head is positioned to the track is the seek time; The time waiting for the disc to rotate to the correct position is called the rotation waiting time. Addressing time is an important indicator for evaluating the performance of mechanical hard disks. This indicator is directly related to the number of hard disk revolutions and the number of heads. The faster the hard disk rotates, the faster the correct sector will be rotated under the head under the same addressing algorithm control conditions. However, the hard disk rotation speed cannot be made infinitely fast, because the faster the hard disk rotation speed, the higher the magnetic surface technology and the main motor technology required, and the noise and temperature generated will increase geometrically. Three speed options are most commonly used on civilian-grade, commercial-grade, and industrial-grade hard drives: 5400 rpm, 7200 rpm, and 10,000 rpm. Number of heads, current mechanical hard disks generally contain multiple platters and use independent heads. The main effect of this is to increase the capacity of the mechanical hard drive while the hard drive density remains unchanged. In fact, this approach can also increase a certain amount of hard disk performance, because when reading files stored on different magnetic surfaces, their seek time can be relatively independent. But its hints on performance can only be limited, because these platters share the same spindle motor. 1U Patch Cord Rear,1U Patch Panel,1U Fiber Patch Panel,1U Patch Cord Rear Axle Huizhou Fibercan Industrial Co.Ltd , https://www.fibercan-network.com
The structure of the mechanical hard disk is quite complicated. There are not only the well-known disk, magnetic head and motor, but also the main shaft, transmission arm, transmission shaft and reaction force return spring device. Of course, there are circuit boards and aluminum protective shells.