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141. 发明专利

JPH04195773A MAXIMUM LIKELIHOOD DECODE CONTROL SYSTEM 失效
公开(公告)号：JPH04195773A
公开(公告)日：1992-07-15
申请号：JP31791790
申请日：1990-11-26
申请人： FUJITSU LTD
发明人： SUGAWARA TAKAO , MIZOSHITA YOSHIBUMI , AIKAWA TAKASHI , MUTO HIROSHI , KASAI KIICHIROU
IPC分类号： G11B20/10 , G11B20/18 , H03M13/23
摘要： PURPOSE:To reduce the error rate of decode without increasing the length of restraint by using a sample value of some bits equivalent to previous one in time series as an assumed sample value from an assumed date row and estimating the extent of interference produced by a future signal. CONSTITUTION:When an attempt is made to compute an assumed sample value based on an assumed data row of an assumed pass memory 4 and add the computed value to an ACS circuit 1, the extent of interference induced by a future signal is estimated by multiplication and addition processing, using 1 bit or several bits of a sample value of an input signal equivalent to previous one in time series from this assumed data row. More specifically, consideration is given to waveform interference between adjoining bits and separated bits by some where an accurate sample value is computed. In this manner, decoding is carried again based on the difference between the assumed sample value and the sample value of the input signal. This construction makes it possible to minimize the error rate of the decode without increasing the length of the assumed data row.

142. 发明专利

JPH03252971A HEAD ACTUATOR FOR DISK FILING DEVICE 失效
公开(公告)号：JPH03252971A
公开(公告)日：1991-11-12
申请号：JP4945390
申请日：1990-03-02
申请人： FUJITSU LTD
发明人： YAMADA TOMOYOSHI , MIZOSHITA YOSHIBUMI
IPC分类号： G11B21/02
摘要： PURPOSE:To make a disk filing device compact and thin by providing two opening parts on the same radius with the fixed shaft of a head actuator as a center, housing fixer coils in the opening parts and covering the opening parts with fixer yokes forming a magnetic circuit while facing the permanent magnet of a movable part. CONSTITUTION:On a base 21a of an enclosure 21, two opening parts 27 and 28 are formed on the same radius with a hole 26, which presses the fixed shaft in, as the center and in the opening parts, flatly wound coils 29 are housed while being paired. Actually, the coils 29 are adhered to doughnut-shaped fixer yokes 30 and housed into the opening parts 27 and 28 by fitting the fixer yokes 30 to the base 21a. Therefore, since an axial flux type motor can be constituted coaxially to the rotary shaft of a carriage 20 and a horizontal projecting area is reduced, the device can be made compact. Thus, a compact head actuator can be manufactured and the device can be made compact and thin.

143. 发明专利

JPH03233609A POSITIONING CONTROL SYSTEM 失效
公开(公告)号：JPH03233609A
公开(公告)日：1991-10-17
申请号：JP2819790
申请日：1990-02-09
申请人： FUJITSU LTD
发明人： HASEGAWA SUSUMU , MIZOSHITA YOSHIBUMI , TAKAISHI KAZUHIKO
IPC分类号： G05D3/12 , B41J19/18 , G11B5/55 , G11B21/08
摘要： PURPOSE:To enable high-speed positioning control by executing the control while expressing the position, velocity and acceleration, etc., of the position control, for which an evaluation function is made minimum, by a polynomial concerning time. CONSTITUTION:A driving part 2 is provided to move and position an object 1 to be controlled, and an arithmetic control part 3 is provided to control this driving part 2 according to digital arithmetic. Based on acceleration and deceleration patterns for which the power integration value of a value differentiating the acceleration of the object 1 to be controlled is made minimum, the arithmetic control part 3 expresses the target position, target velocity and target acceleration by the polynomial concerning the time and by using the polynomial, the driving part 2 is controlled corresponding to an arithmetic result for every sample time and the difference of the position, velocity and acceleration for the object 1 to be controlled at every sample time. Thus, the acceleration and deceleration can be controlled without generating vibration at the object 1 to be controlled or the driving part 2, and the positioning control can be accelerated.

144. 发明专利

JPH02246067A SLIDER FOR MAGNETIC DISK DEVICE 失效
公开(公告)号：JPH02246067A
公开(公告)日：1990-10-01
申请号：JP6597289
申请日：1989-03-20
申请人： FUJITSU LTD
发明人： YONEOKA SEIJI , MIZOSHITA YOSHIBUMI , TAKAHASHI MINORU , OE TAKESHI
IPC分类号： G11B21/21
摘要： PURPOSE:To suppress the occurrence of a floating force, to spread rail width, and to improve durability in contact start/stop(CSS) by forming the plate type slider of a floating type magnetic head so as to narrow the rail width advancing from the inflow terminal to the outflow terminal of the air. CONSTITUTION:An electromagnetic conversion element 11 is loaded on the rear part of a slider 10, and the rail width (w) is formed so as to be narrowed advancing from the inflow terminal 12a to the outflow terminal 12b at a rail plane by forming steps on another part. At such a case, as for the pressure distribution of the rail plane 12, a pressure center exists almost in the center of the rail plane as shown in cureve A, which narrows down the rail width at the outflow side. In such a way, the floating force can be reduced, and the rail width can be taken widely, and the durability in the CSS can be improved.

145. 发明专利

JPH02239484A HOLDING MECHANISM FOR MAGNETIC DISK 失效
公开(公告)号：JPH02239484A
公开(公告)日：1990-09-21
申请号：JP5974189
申请日：1989-03-14
申请人： FUJITSU LTD
发明人： YAMADA TOMOYOSHI , IMAMURA KOJI , MIZOSHITA YOSHIBUMI
IPC分类号： G11B23/03 , G11B17/038 , G11B23/00
摘要： PURPOSE:To prevent a magnetic disk from being deformed and damaged by providing a flange to support the inner circumferential part of the magnetic disk in a lower direction and a spring means to press the upper surface of the magnetic disk in a ring-shaped member to be overlapped in multiple steps and to be inserted to a spindle. CONSTITUTION:In a ring-shaped member 20 to be overlapped in the vertically multiple steps and to be inserted into a spindle 6, a flange 21 is provided to support the inner circumferential part of a magnetic disk 10 in the lower direction and a spring means 22 is provided to press the upper surface of the magnetic disk 10. Each magnetic disk 10 is clamped by pressing force, which is generated by the deflection of the spring part 22. However, the clamp force is made enough to be more than force to generate friction force resisting against force caused by a product between quantity for one magnetic disk and acceleration to be applied to this disk or product between inertia moment and angular acceleration. Since the ring-shaped member 20 is made enough thick, the deformation caused by the clamp force is reduced. Thus, the deformation of the magnetic disk and the damage of the glass disk can be prevented.

146. 发明专利

JPH02227886A HEAD POSITIONING MECHANISM 失效
公开(公告)号：JPH02227886A
公开(公告)日：1990-09-11
申请号：JP4958589
申请日：1989-02-28
申请人： FUJITSU LTD
发明人： YAMADA TOMOYOSHI , MIZOSHITA YOSHIBUMI
IPC分类号： G11B21/16 , G11B21/10
摘要： PURPOSE:To execute a highly accurate positioning and a high-speed access by installing a main actuator to execute an access in a coarse mode and a sub-actuator to be swayingly operated in a fine mode between an access arm and an in-line supporting spring. CONSTITUTION:On plural sheets of magnetic disks 4, sub-actuators 9 and 11 with comparatively high rigidity and light weight are provided in which a sway center member 7 and a pair of piezoelectric elements 8a and 8b displaced in a mutually reverse direction at both sides are made to intervene between a head supporting spring mechanism 3 to support respective magnetic heads 5 and an access arm 2 separately from a sway type main actuator 1 to simultaneously move magnetic heads 5, respectively. All magnetic heads 5 are simultaneously access operated in the coarse mode by the main actuator 1, and thereafter, individual magnetic heads 5 are independently trackingly controlled to the goal tracks in the fine mode by the sub-actuators 9 and 11. Thus, the highly accurate positioning and high-speed access can be executed.

147. 发明专利

JPH02166603A MAGNETIC RECORDING AND REPRODUCING DEVICE 失效
公开(公告)号：JPH02166603A
公开(公告)日：1990-06-27
申请号：JP32038788
申请日：1988-12-21
申请人： FUJITSU LTD
发明人： SUGAWARA TAKAO , AIKAWA TAKASHI , MUTO HIROSHI , KASAI KIICHIROU , MIZOSHITA YOSHIBUMI
IPC分类号： G11B5/09
摘要： PURPOSE:To enable the demodulation of a reproduction signal without deteriorating an S/N by executing the band limitation of the reproduction signal from a magnetic recording medium at the max. frequency of the reproduction signal. CONSTITUTION:This device consists of an integrating circuit 1, an AD converter 2, a differentiator 3, and a demodulator 4. The integrating circuit 1 integrates the reproduction signal from the magnetic recording medium and the AD converter 2 samples the output signal from the integrating circuit 1. The differentiator 3 differentiates the output signal from this AD converter 2 and the demodulator 4 arithmetically processes the output signal of the differentiator and demodulates the information. The signals reproduced by a magnetic head from the magnetic recording medium are, therefore, integrated by the integrator 1, are sampled by the AD converter 2 at the time interval Tbit (the bit time interval of the recording information included in the reproduction signal S from the magnetic recording medium), are differentiated by the differentiator 3, and are demodulated by the demodulator 4 to form reproduction information of '1', '0'. The demodulation of the reproduction signal is executed in this way without deteriorating the S/N.

148. 发明专利

JPH0256782A FIXING STRUCTURE FOR MAGNETIC HEAD ARM 失效
公开(公告)号：JPH0256782A
公开(公告)日：1990-02-26
申请号：JP20645688
申请日：1988-08-22
申请人： FUJITSU LTD
发明人： YAMADA TOMOYOSHI , ARIGA TAKAHARU , MIZOSHITA YOSHIBUMI , IMAMURA TAKAHIRO , SUZUKI NORIHIKO
IPC分类号： G11B21/16 , G11B21/02
摘要： PURPOSE:To surely fix an arm by providing a clamp with the background of a groove supported at a cantilever as a pressing point and pressing a groove part backsurface by the clamp. CONSTITUTION:At a carriage 21, grooves 22 and 23 supported by sandwiching an arm 20 to the right and left of the tip are formed, the root of one side groove 22 is formed in a cantilever shape and at the tip, the groove 22 is supported. As a means to pressurize the background of the groove 22, a clamp 25 with the background of the groove 22 as the pressing point is provided. For the clamp 25, the center is pressed with a bolt 26 which penetrates a cantilever 24 and is screwed into the carriage 21. The arm 20 inserted into grooves 22 and 23 can be fixed by tightening the bolt 26. Thus, the groove 22 is adhered to the arm 20 and the arm 20 can be surely fixed to the carriage 21.

149. 发明专利

JPH01307064A MAGNETIC HEAD POSITIONING CONTROL SYSTEM 失效
公开(公告)号：JPH01307064A
公开(公告)日：1989-12-12
申请号：JP13791788
申请日：1988-06-03
申请人： FUJITSU LTD
发明人： YAMADA TOMOYOSHI , MIZOSHITA YOSHIBUMI , ARIGA TAKAHARU , MAETA HIROSHI , SUZUKI NORIHIKO
IPC分类号： G11B21/02 , G05D19/02
摘要： PURPOSE:To cancel the oscillation mode of a flat type moving part and to increase the head positioning accuracy by conducting respective different driving currents to two flat type twisting coils and generating a moment. CONSTITUTION:In the cavity magnetic field in a magnetic circuit composed of permanent magnets 43a-43d and a yoke, a flat type carriage 44 to support a magnetic head slider by ahead arm 46 and a moving part 45 to provide flat type twisting coils L1 and L2 symmetrically to both front and rear surfaces of the gravity center position are arranged. When the magnetic head positioning is executed by the linear movement of the moving part 45, by conducting the respective different driving currents to both coils L1 and L2, the moment is generated and the oscillation to occur at the moving part 45 is suppressed.

150. 发明专利

JPH0146939B2 失效
公开(公告)号：JPH0146939B2
公开(公告)日：1989-10-11
申请号：JP15860379
申请日：1979-12-06
申请人： FUJITSU LTD
发明人： MIZOSHITA YOSHIBUMI
IPC分类号： G05D3/12 , G11B5/55 , G11B21/08

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