Matsushita Electric Industrial Co., Ltd.

Matsushita Electrical Industrial Co., Ltd.

Saburo Kubota

Tutomu Sakurai

Yoshifumi Hara

Hirotaka Mega

Masaki Suzuki

Keishi Kubo

Hiroyuki Nagano

Satoshi Tanaka

Katsuhiro Kida

Hiroshi Fujiwara

Yasuhiro Kametani

Masanobu Miyata

Masaru Kishimoto

Yoshihumi Hara

Keishiro Ota

Tetsuya Shiizaki

Akira Ihara

An RF signal is read from a rewritable DVD while rotating the rewritable DVD. The read RF signal is converted to pulse signals according to different threshold values, and the number of pulses of each pulse signal is counted. Indexes IBSmin, IBMmax, IBS, and IBRmax are determined from the relationship between the counted numbers and the threshold values, and the recording quality of the BCA on the rewritable DVD is evaluated by judging whether these indexes satisfy the following inequalities:max/min&#x2266;0.8max/&#x2266;1.5

BCA evaluation device and method for rewritable DVDs with different threshold value pulse signals

A double spindle synchronous driving apparatus for synchronously driving first and second spindles, including: first and second motors for driving the first and second spindles, respectively; first and second rotational detection members for detecting rotational positions of the first and second motors so as to output first and second detection signals, respectively; first and second deviation counters which outputs first and second deviation signals in response to a position command signal and the first detection signal and in response to the position command signal and the second detection signal, respectively; a correction member which formulates first and second correction signals for the first and second deviation signals, respectively in accordance with a difference between the first and second deviation signals by fuzzy inference; first and second arithmetic members for performing arithmetic operation of the first deviation signal and the first correction signal and of the second deviation signal and the second correction signal so as to output first and second control signals, respectively; and first and second drive members for driving the first and second motors on the basis of the first and second control signals, respectively.

Double spindle synchronous driving apparatus

A fault examining apparatus is provided in a loop network system, in which a master station is connected sequentially with a plurality of follower stations in a loop transmission path to transfer digital optical signals denoting serial data information from the master station to the follower stations, from the follower stations to the follower stations or from the follower stations to the master station. The apparatus includes a device for detecting and storing a present value, a maximum value and a minimum value of a peak level value of received optical signals, and a display device for displaying the values.

Fault examining apparatus for loop-shaped data transmission system using

A bi-axial synchronous driving apparatus which includes: a set of motors for respectively driving two axes; rotation detecting devices for detecting rotational positions of the respective motors; a set of deviation counters to which a common position instruction signal and detection signals of the respective rotation detecting devices are applied; a correcting unit to which deviation signals outputted from the respective deviation counters are applied, so as to form correction signals with respect to the respective deviation signals based on an integration of a difference between each one of the deviation signals and the other corresponding deviation signal; a set of adding devices for adding the deviation signals outputted from the respective deviation counters to the correction signals; and a set of driving devices for driving the respective motors based on control signals outputted from said respective adding devices.

Bi-axial synchronous driving apparatus

When an input data of a slave station makes any change, the slave station transmit a serial information (in serial data frame, FIG. 2) which is made by altering an information continuously transmitted from a master station into a serial information to be transmitted by interrupt, which serial information includes a start information (in start bit), interrupt information (in interrupt field), address information (in address field) of this slave station and data information (in data field) produced in this sub-station responding the change, and it is transmitted by the interrupt; therefore the master station can find the interrupt-transmitted serial information among many serial informations sent back thereto, and the slave station can immediately transmit the change to the master station without wasting time by waiting for one turn scanning of all the slave stations.

Data transmission apparatus

A velocity signal is obtained by calculating both the selected signal of the differentiated signal of the position signal from a position detector and the selected signal of the sinusoidal wave signal according to position displacement, so that a velocity detection produces a smaller velocity detection error at a low velocity and generates no ripple component even when a high velocity is detected.

Velocity detector for detecting velocity from position detector

In a data transfer apparatus, as one substation in a loop type signal transfer system, e.g. for use in an automatic machine, synchronization information and address information are received and the address is checked by an address coincidence circuit; when address coincidence is detected the data information in the received signal is replaced by serialized data which is contrived by parallel-serial conversion of the parallel input data at the substation; therefore there is no need of once storing the entire received signal transferred, and therefore, high speed data transfer results.

Data transfer apparatus

Mechanical vibration of a rotating test body is translated into a periodic signal which represents a combined vector of the unbalance means of the rotating body and the mechanism that rotates it. The periodic signal is divided into two orthogonal vector components. The magnitude of the two vector components are converted into digital signals and applied to a computer. Unknown values of four constants are determined by a preliminary test having three successive stages. In the first and second stages the test body is rotated to register the digital signals; in the second state the angular position of the test body is displaced a predetermined amount with respect to its first stage position. In the third stage of the test, a trial dead weight of a known mass is mounted on the test body and rotated to register the digital signals. The computer operates on the registered digital signals to determine the four constants in accordance with a set of equations. After the preliminary test, the data registered in the first stage of the preliminary test is substituted into another set of equations using the four constants to determine the dynamic unblance mass and its angular location.

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Katano, Japan

Saburo Kubota