Abstract: A Pb-free soldering alloy that does not include any Pb is provided. The soldering alloy prevents Cu present in a printed-circuit board from combining with Ni in the soldering alloy at the soldered part, prevents Cu from precipitating and diffusing in the soldering alloy, suppresses the generation of fine cracks at the soldered part and increases the mechanical strength of the soldered part. The Pb-free soldering alloy contains 3.5 to 6.0 wt. % Ag, 0.001 to 1.0 wt. % Ni and Sn for the balance.

Abstract: Pb-free soldering alloy that does not include any amount of Pb is proposed.

Abstract: A thinned DC brushless motor (50) has a base plate 52 of magnetic material, a rotatable shaft (58) supported perpendicular to the base plate, an annular hub (68) coaxially fixed on the shaft, a stator (60) fixed on the base plate, and a rotor (70) coaxially fixed on the shaft through the annular hub. The rotor (70) includes an first wall portion (72) extended radially from the shaft above the stator and parallel to the base plate and a second wall portion (74) extended from a peripheral edge of the circular potion towards the base plate to enclose the stator. An annular magnet (78) is fixed on an inner surface of the second wall of the rotor with leaving a small gap from a peripheral edge of the stator. The upper wall has a bent portion (80) extended outward away from the annular magnet in the vicinity of an inner edge of the annular magnet.

Abstract: A spindle motor includes a printed wiring board. A stator is fixed to the printed wiring board. A housing is fixed to the printed wiring board. A bearing is provided on the housing. A rotor shaft is rotatably supported by the bearing. A hub base is mounted on the rotor shaft. A stator winding provided on the stator is bonded to the printed wiring board. The stator may have an inner circumferential portion formed with a plurality of grooves. In this case, it is preferable that the printed wiring board has a plurality of through holes at positions corresponding to positions of the grooves in the stator.

Abstract: In a method for manufacturing yokes (3, FIG. 1) to be used in a permanent magnet type stepping motor (10, FIG. 2), a surface-treated dead soft steel sheet such as nickel-plated steel sheet or aluminized steel sheet containing carbon in 0.01 wt. % or less is press-worked to form yoke (3) having plural pole teeth (3a, FIG. 1) on its inner periphery, and then the yoke is annealed in an inactive gas atmosphere in a temperature range of 750.degree.-820.degree. C. to remove residual stress, and permeability of the yoke is improved.

Abstract: In a method for manufacturing yokes (3, FIG. 1) to be used in a permanent magnet type stepping motor (10, FIG. 2), a surface-treated dead soft steel sheet such as nickel-plated steel sheet or aluminized steel sheet containing carbon in 0.01 wt. % or less is press-worked to form yoke (3) having plural pole teeth (3a, FIG. 1) on its inner periphery, and then the yoke is annealed in an inactive gas atmosphere in a temperature range of 750.degree.-820.degree. C. to remove residual stress, and permeability of the yoke is improved.

Abstract: An echo canceller includes a first transversal filter for generating a first echo canceling signal to be canceled from an output signal from a sampler, the first echo canceling signal corresponding to a first sampling value of an echo response waveform of an echo path by a sampling clock when no sampling clock jitter occurs, a second transversal filter for generating a second echo canceling signal corresponding to a difference between the first sampling value and a second sampling value when the sampling clock jitter occurs, two subtractors for canceling the first and second echo canceling signals from a digital reception signal output from the sampler, and a controller for detecting the sampling clock jitter and performing a control operation such that a tap coefficient value of the second filter is added to a tap coefficient value of the first filter to update the tap coefficient value of the first filter, and thereafter, the second echo canceling signal generating operation of the second filter is disabled

Abstract: An echo canceller of this invention cancels an echo signal input to a sampler through an echo path upon 2-wire/4-wire conversion. The echo canceller includes a filter having a characteristic for reducing a tail of an echo response waveform and inserted between an output terminal of the sampler and a reception output terminal, a first transversal filter for generating a first canceling signal for canceling an echo signal sampled at equal sampling clock intervals after the echo signal passes through the filter, a second transversal filter for canceling a deviation of a sampling value obtained when sampling clock is jittered before the deviation passes through the filter, an enable/disable unit for enabling/disabling a tap output of the second transversal filter, and a controller for, from a moment at which the sampling clock is jittered, controlling the enable/disable unit to cancel a deviation in correspondence with a deviation value of an actual sampling value.