摘要:
An optical information recording medium (1) is composed of a pit recording area (2), wherein various control information is recorded by a prepit, and a user recording area (3) having a guide groove formed in a groove format, and a phase depth for the prepit and the groove are approximately the same wherein the phase depth is less than or equal to λ/10, wherein λ is a wavelength for reproducing light source. A recording/reproducing apparatus (4) for the optical information recording medium (1) includes decoding means (12) for decoding information by detecting a tangential push-pull reproduced signal from the prepit recording area (2) and detecting an aggregated signal from the user recording area (3).
摘要:
A resampling DPLL estimates a signal outputted from a pickup through an AGC and outputs a signal of the estimation result. A transversal filter in an adaptive equalizing circuit equalizes in waveform the signal outputted from the resampling DPLL. An error signal is detected from the equalized waveform outputted from the transversal filter. The error signal is fed back to the transversal filter so as to control the transversal filter such that the error signal becomes minimum.
摘要:
In a data decoding apparatus that performs decoding of recorded data played back from a recording medium by Viterbi decoding according to a decoding trellis based on a recording signal characteristic, a pathmetric calculation circuit has run length counters (20) and (25) for detecting the run length of recorded data, a target value control circuit (1) for varying the target value used for metric calculation of Viterbi decoding based on run length information, and a monitoring means, provided in the target value control circuit (1), for protecting against faulty operation caused by using a count value that should not be used as an information source.
摘要:
A linear equalizer unit sequentially subjects a signal to be processed to linear equalization. A temporary decision unit sequentially subjects a signal subjected to linear equalization by the linear equalizer unit to temporary decision. A nonlinear equalizer unit derives a plurality of coefficients using a signal subjected to temporary decision as a teacher signal and sequentially subject a signal subjected to linear equalization by the linear equalizer unit to nonlinear equalization based on the plurality of coefficients.
摘要:
A linear equalizer unit sequentially subjects a signal to be processed to linear equalization. A temporary decision unit sequentially subjects a signal subjected to linear equalization by the linear equalizer unit to temporary decision. A nonlinear equalizer unit derives a plurality of coefficients using a signal subjected to temporary decision as a teacher signal and sequentially subject a signal subjected to linear equalization by the linear equalizer unit to nonlinear equalization based on the plurality of coefficients.
摘要:
A tensioner for a chain or similar power transmission medium comprises a spring-biased plunger having annular rack teeth with gradually sloping forward surfaces and steeper rearward surfaces. The teeth are engaged by radially movable balls received in inclined grooves in an axially movable annular ball seat disposed in an annular groove formed in the wall of a plunger-accommodating hole in a tensioner housing. The bottoms of the inclined grooves face a steep rearward surface of a rack tooth, and the annular ball seat is axially movable in the annular groove and biased in the plunger protruding direction by a spring that exerts a biasing force greater than the biasing force exerted on the plunger. The balls and the movable annular ball seat block retraction of the plunger on engine start-up, but permit retraction when excessive force is imparted to the plunger while the plunger is in a protruding condition.
摘要:
An elongated stationary guide for a traveling transmission chain in an engine such as a timing chain has a narrow reinforcing groove formed along the longitudinal direction of a metal base plate of the guide by surface-pressing, whereby the base plate exhibits plastic deformation. The narrow reinforcing groove extends toward the ends of the base plate past the locations at which the base plate is mounted on an engine block by mounting bolts.
摘要:
In a chain tensioner, an expansible ring is disposed in an internal groove formed in the inner wall of a plunger-accommodating hole near an open end thereof. The ring cooperates with grooves formed on the plunger to exert a ratchet action. The relationship between the angles of the surfaces of the internal groove and the grooves on the plunger allows the plunger to protrude, restricts retraction of the plunger on start-up of a chain transmission, but allows retraction when chain tension becomes excessive. In one embodiment, in which the ring is a C-ring, the tensioner housing can be formed with external threads for mounting in a threaded hole on a timing chain cover or other engine part. In other embodiments, the ring can have externally protruding levers for manipulation of the ring.
摘要:
A chain guide is composed of a resin shoe engageable with an aluminum base frame. The shoe has a hook formed at a chain entry end for engagement with a chain entry end of the base frame, and a C-shaped hook at the chain exit end engageable with a side edge of the base frame. The shoe is engaged with the base by first engaging the C-shaped hook with the side edge of the base frame, then flexing the chain entry end of the shoe until the hook at the chain entry end can receive the chain entry end of the base. The shoe is moved a short distance toward the chain exit end of the base until a projection formed on a back surface of the shoe near the chain entry end snaps into a depression formed on a front surface of the base frame, locking the shoe and base together.
摘要:
In a ratchet tensioner, a pawl, pivoted on a shaft in the tensioner housing, engages teeth on a plunger protruding from the housing to allow protruding movement of the plunger, while limiting retracting movement to a backlash distance. The pawl is biased into contact with the teeth on the plunger by a spring disposed in a hole in the housing and acting, through a piston slidable in the same hole, against a convexly curved surface of the pawl. The piston has a reduced portion in engagement with the pawl, which allows the pawl to be miniaturized without excessively reducing the radial dimensions of the portion of the pawl surrounding the pivot shaft.