Sony Corporation

Akebono Brake Industry Co., Ltd.

Other

Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Electric Engineering Company, Limited

Tgk Co., Inc.

Satoshi Kusaka

Hiroshi Yamamoto

Toshiya Suzuki

Koji Suzuki

Yujiro Ito

Satoshi Narumi

Shinji Saeki

Kuninori Shino

Shunichi Kondoh

Katsuji Seki

Yoshiyuki Sugai

Hiroyuki Tamagawa

Masaharu Hoashi

Ryousuke Yoshihiro

Hidetoshi Hishinuma

Yuki Muroya

Yoichi Onda

Kiyokazu Takakuwa

A friction material includes a fiber base material, a friction modifier and a binder. The friction modifier includes two or more kinds of non-whisker-like titanate compounds. The non-whisker-like titanate compound includes non-whisker-like lithium potassium titanate. The friction material includes no copper component. Alternatively, a friction material includes a fiber base material, a friction modifier and a binder. The friction material includes a non-whisker-like titanate compound and a low-melting-point metal fiber. The friction material includes no copper component.

Friction material

A friction material including two or more kinds of titanates and a ceramic fiber. The friction material includes no copper component. The two or more kinds of titanates may optionally include two or more kinds of alkali metal titanates, or the two or more kinds of titanates may optionally include an alkaline earth metal-alkali metal titanate and an alkali metal titanate.

In a friction material, columnar or scaly non-whisker-like alkali metal titanate or non-whisker-like alkali metal&#x2022;alkaline-earth metal titanate having an average particle diameter in the range of 0.1 to 100 &#x3bc;m and an aspect ratio of 3 or less and an inorganic porous filler are compounded, and a friction material in which non-whisker-like lithium.potassium titanate having an average particle diameter in the range of 0.1 to 100 &#x3bc;m and an aspect ratio of 3 or less is compounded.

A motor driving circuit includes an induced voltage detecting circuit for detecting induced voltages in a motor; a rotation speed/phase detecting circuit and an output matrix circuit for generating a plurality of control signals in response to the detection result of the voltage detecting circuit; a current control circuit for generating current control command values in response to the control signals; and a current detecting circuit for detecting output currents that are driving the motor, and for controlling output transistors in response to its detection result and the current control command values. The motor driving circuit can sharply reduce the driving noise of the motor with improving the efficiency of the motor drive by shaping the output currents in a sinusoidal waveform.

Motor driving circuit

An object is to realize acoustic noise reduction under a wide range of rotating speeds and together with PWM control. A signal (VCTL,) is generated as a trapezoidal wave repeatedly rising and falling in each given electrical angle section extending before and after the current-supply pattern is switched in accordance with the electrical angle of a rotor of a motor, and a signal (VCTL,) is generated in the opposite phase. A control circuit (,) appropriately selects among the signals (VCTL,and VCTL,) and a given signal (SCTL) and inputs them to comparators (,to,). The comparators (,to,) compare the input signals with a carrier signal (B,) provided as a triangular wave. Switch elements for controlling the current-supply pattern to the motor turn on/off on the basis of output signals (C,to C,) from the comparators (,to,). As a result, the current-supply pattern is switched softly by PWM control in the electrical angle section mentioned above.

Motor driving apparatus

It is an object to enable efficient driving even if the rotation speed is variable in a driving circuit for a DC brushless motor having no position detection. The counterelectromotive force of the motor M is received by the comparators (201-203) and the trigger signals (G1 and G2) are outputted with 120.degree. cycle in synchronization with the rotation. Two oscillation signals (N1 and N2) in synchronization with the rotation of the motor are generated therefrom and a serial control signal (CNT) which becomes active/inactive for every 30.degree. is further produced in the 30.degree. signal operation circuit (104). The control signal (CNT) is serial/parallel converted into conversion control signals (L1-L3) in the 180.degree. signal conversion circuit (105). The 120.degree. switching circuit (1116) further converts them into driving signals (K1-K6) and applies them to the current control portion (300). The motor is driven by a signal delayed by a rotation angle of 30.degree. not according to the number of rotation of the motor.

A color video printer has a liquid crystal body acting as a shutter extending across a color printing paper. The liquid crystal body includes a first shutter array for a first color, a second shutter array for a second color, and a third shutter array for a third color, and an electrical arrangement for supplying first, second, and third color signals to the respective first, second, and third shutter arrays. Relative motion between the liquid crystal body and the color printing paper is provided in a direction to cause the liquid crystal body to scan the paper.

Printer

In an optical atmospheric link system for transmitting a light beam carrying an information signal between a transmitter and a receiver which is located apart from the transmitter, the transmitter includes a light source for generating the first light beam modulated with the information signal, a first optical system for transmitting the light beam toward the receiver, a second optical system for turning at least a portion of the light beam, and a third optical system for observing the light beam turned by the second optical system and the receiver. Also, the receiver includes a first detector for receiving the first light beam transmitted from the transmitter through the first optical system, detecting a relative position of the first light beam received and the receiver and for generating a position error signal, a second light source for generating a second light beam modulated with the position error signal, and a second optical system for transmitting the second light beam generated by the second light source toward the transmitter, wherein the transmitter further includes a second detector for receiving the second light beam transmitted from the receiver through the second optical system and demodulating the second light beam to obtain the position error signal, and a position control circuit for controlling a position of the transmitter according to the position error signal obtained by the second detector so that the light beam is directed toward the receiver.

Optical atmospheric link system

An image input apparatus is disclosed, which comprises a running roller manually rolled along an image information surface for the scanning thereof, position detecting means for detecting the position of the running roller according to the rotation thereof, a line sensor for reading out image information of the image information surface, a line sensor driving circuit for driving the line sensor according to a control pulse signal having a constant cycle period, and memory means for storing the output of the line sensor. The output of the position detecting means is utilized as address data of a memory to accurately store image information in the memory.

Image input apparatus

A pickup assembly for a disc player includes a magnetic circuit for generating magnetic fluxes perpendicular to each other, a first coil group through which a current flows in a direction perpendicular to the magnetic fluxes, a second coil group through which a current flows in a direction perpendicular to one of the magnetic fluxes, a third coil group through which a current flows in a direction perpendicular to the other of the magnetic fluxes, a bobbin on which the first, second and third coil groups are wound, and a supporting member for supporting the bobbin so as to be movable in the three ways as along X-, Y- and Z axes.

Pickup assembly for disc player

Apparatus for controlling a tone arm in a record playing device of the linear tracking pickup type includes a pair of guide rails; a carriage slidably mounted on the guide rails; a pickup assembly mounted on the carriage and including a support mechanism for supporting the tone arm for horizontal movement with respect to a record disc; a linear drive motor for linearly driving the carriage along the guide rails in the horizontal direction with respect to the record disc; a motor drive circuit for controlling the energization of the linear drive motor; an offset angle detecting device for detecting an offset angle of the tone arm and for generating an offset angle output in response thereto; a first switch circuit for supplying the offset angle output to the motor drive circuit when the tone arm traces the record disc to drive the linear drive motor so as to compensate for the detected offset angle; an inclination detecting circuit for detecting an inclination of the carriage with respect to the record disc and for generating an inclination output in response thereto; and a second switch circuit for supplying the inclination output to the motor drive circuit when the tone arm is lifted from the record disc to prevent undesirable linear movement of the carriage.

Arm driving device in linear tracking pickup apparatus

Apparatus for controlling a tone arm is provided with a horizontal drive motor for moving the tone arm in the horizontal direction, a horizontal velocity detector connected to the same rotating shaft as the tone arm so as to move concurrently with both the tone arm and the horizontal drive motor, a control circuit having a motional feedback loop to energize the horizontal drive motor in accordance with a desired pre-set velocity signal and a fedback detected velocity signal.

Tone arm assembly

A tone arm assembly provided with a motor for moving a tone arm in a horizontal direction with respect to a record disc, a servo circuit for keeping the moving velocity of the tone arm constant, and a positioning servo circuit to operate when the tone arm reaches a reproducing position, in which the positioning servo circuit and the velocity controlling servo circuit are combined together thereby to stop the tone arm quickly at a predetermined position.

Growing community of inventors

Tokyo, Japan

Satoshi Kusaka