Abstract: A servo control system includes an error amplifier for deriving an error signal representing the displacement of a focus point of laser beam from different planes of an optical record disc, a differentiator for differentiating the error signal to detect its rate of variation, and a comparator for detecting the maximum peak of the differentiated signal which corresponds to reflections from the plane on which information is recorded. The focus point is moved in a direction toward the disc in an open loop mode until the maximum peak of the differentiated signal is detected, whereupon the focus point is controlled in response to the error signal in a closed loop mode to keep track of the recording plane.

Abstract: An input signal is applied to a clamping circuit where the level of the input signal is clamped at a desired base line voltage in response to a clamping control signal. The clamping control signal is a pulse train signal, and pulses are applied to the clamping circuit only when the level of the output signal of the clamping circuit is within a given range. Therefore, when the level rising rate or speed is low, the level of the input signal is intermittently clamped so that the output signal level is maintained close to the base line voltage. When the level rising rate exceeds a given value, clamping is not performed so that the output level follows the input level. In order to see whether the level of the output signal is within the given range or not, a reference voltage which is higher than the base line voltage is used when shaping a two-level signal. If the input signal is of three-level, another reference voltage, which is lower than the base line voltage, is additionally used.

Abstract: In order to prevent clogging of the nozzle of an ink jet writing head, a nozzle moistening device is provided which includes an elastic enclosure fluid-tightly engageable with the front face of the writing head when not in use, a source of water, and a capillary tube for transmitting water from the source to the enclosure by capillary action to permit evaporation of water in the enclosure to moisten the nozzle.

Abstract: A coaxial type microwave filter having an outer conductor and at least one inner conductor supported in the outer conductor has a strip transmission line extending from an external strip-line circuit to the inner conductor through an opening in the outer conductor. The strip transmission line includes a dielectric member forming an integral part of the dielectric substrate of the external circuit and a thin layer of conductive strip also forming an integral part of the conductive film pattern of the external circuit. The extending strip transmission line is electromagnetically coupled with the inner connector to permit the two microwave circuits to be interconnected with no use of a connector.

Abstract: A method for making a carbide thin film thermistor which comprises providing an insulating substrate, forming at least one pair of electroconductive electrodes on the substrate in a desired pattern, and forming a carbide resistor film on the insulating substrate and the electroconductive electrodes by sputtering process while leaving part of the electrodes exposed for external connections. A carbide target material is sputtered in an inert gas atmosphere containing a small amount of an impurity gas. The thermistor element is arbitrarily controlled to have a desired level of resistance by choice of the impurity gas, the amount of such gas and the mode of sputtering. Optionally, the element is trimmed to adjust its resistance accurately and is also hermetically sealed within a glass tube to prevent the element from being contaminated with harmful substances.

Abstract: An ink jet writing head includes a housing shaped to provide an inner liquid chamber for containing ink therein, a piezoelectric transducer for generating short-duration pressure rises in the liquid in the inner chamber, and an outer liquid chamber which is separated by a dividing plate from the inner liquid chamber and connected thereto by a connecting channel formed in the dividing plate. The outer liquid chamber is of such an axial dimension that it may provide capillary action on the ink supplied from an ink supply source. The outer chamber is formed by an ink nozzle plate secured to a surface of the housing spaced from the dividing plate. The ink nozzle is axially aligned with the connecting channel to cause the ink in the outer chamber to leave the writing head in response to the pressure rise in the inner chamber.

Abstract: An induction heat cooking apparatus includes an inverter which generates ultrasonic frequency energy for heating a magnetic load by induction, and a small load detection circuit. The detection circuit includes a comparator which compares the input and output parameters of the inverter and latches a bistable device when the input power is smaller than the output parameter. The bistable device shuts down the inverter to prevent inadvertently placed small utensil objects from being excessively heated.

Abstract: In a self-training biofeedback system, a physiological signal representing the state of relaxation of a person using the system is applied to a time counter to generate a binary count output representing the relaxation period. A visual indicator connected to the time counter provides the self trained person with a quick display of the measured time period so he can gauge the depth of his relaxation.

Abstract: There is described an alloy metal hydride for storing and releasing hydrogen at predetermined temperatures and pressures intended for storing and transporting said hydrogen and also for use as a hydrogen supply source of a fuel cell and fuel electrode. The alloy of this invention consists of 30 to 80 percent by weight Ti and 20 to 70 percent by weight Mn having a high dissociation pressure, easy hydrogen activation, low heat of formation of hydrides and a very fast rate of absorption and desorption, also the alloy is of light weight and of low cost, therefore being of great industrial use.

Abstract: A catalyst for purifying an exhaust gas comprising a carrier substantially composed of calcium aluminate and titanium oxide. The carrier is deposited with a platinum group metal or a metal oxide capable of oxidizing reductive gases into innoxious ones. The titanium oxide is applied on the surface of the carrier or incorporated in the carrier. The carrier may further comprise a transition metal oxide showing catalytic activity. A method of making a catalyst is also disclosed in which titanium oxide is applied on the surface of a solid mass of calcium aluminate.

Abstract: A conductive device using a conductive polymer composition which comprises a mass of a conductive polymer composition in which a conductive charge transfer complex is contained in a polymer matrix and at least a pair of electrodes electrically connected to the mass, at least one component of said complex being contained in or in the vicinity of at least one of the electrodes.

Abstract: A sector scan ultrasonic imaging system comprises a source of a plurality of square wave pulse trains each being delayed by a unit quantization time with respect to adjacent trains, and a plurality of transmitter circuits corresponding to the elements of a transducer array. The duration of each square wave pulse is an integral multiple of the unit quantization time interval. Each transmitter circuit includes a read only memory in which a set of different digital delay time data is stored for the corresponding transducer element and is arranged to be retrieved in response to each angle increment of the ultrasonic beam transmitted from the array. Further included are a data selector for selecting a pulse train in response to a pulse train selection data retrieved from the memory and a programmable counter for counting the pulses of the selected train to generate an output in accordance with a pulse selection data retrieved from the memory.

Abstract: 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.

Abstract: A hermetic motor compressor comprises a casing which includes a dome-like upper casing and a dome-like lower casing. Each of the upper and lower casings has an engagement portion for telescopically engaging with each other. The stiffness of the upper casing is increased by making at least three corner portions close to the engagement portion. Crescent-shaped portions, curved surfaces, an apex portion and crest lines are also provided for the upper casing. This specific structure of the upper casing may be made also for the lower casing, and when both of the upper and lower casings have such construction, the corner portions of the upper casing and the corner portions of the lower casing are arranged alternatively so that the vibrating modes of respective casings offset each other. The shape of the entire casing may be spherical or ellipsoidal.

Abstract: An original image field is successively scanned along each of parallel line paths to detect the image density of the scanned elemental picture area. A plurality of recurring sequences of binary digits or pulses is generated for each of the scanned line paths in synchronism with the scansion of each elemental picture area, thereby forming dot pattern conversion matrices corresponding in number to the number of discrete gradation steps or image densities with the pulses representing the dots in each matrix. The detected image density is used to select a corresponding one of the dot pattern matrices to represent the scanned area with a dot if the latter is present in a specified position in the corresponding matrix by allowing the selected recurring pulse sequence to be delivered to a recording unit which is moved with respect to a recording field in synchronism with the scansion of the original field.

Abstract: A method for making a selective absorption film for solar energy which comprises immersing aluminum or its alloy in water which contains at least two members selected from phosphate ions, fluoride ions and triethanolamine, and optionally ions of a metal selected from copper, iron, cobalt, silver and a mixture thereof thereby forming a chemical conversion film which shows a great absorptivity and a small emissivity.

Abstract: Mental activity of a human subject is indicated with electrodes placed on the head of the subject to respond to brain activity. The electrodes derive a signal including low and high frequency a.c. components respectively having frequency ranges in the same low frequency range as alpha waves derived by the brain and considerably higher than the highest frequency of the alpha waves. The high and low frequency amplitude components are supplied to an indicator arranged so the mental state activity is indicated only in response to the detected high frequency component having an amplitude less than a level indicative of the subject not being in a state of relaxation and the detected low frequency component having an amplitude greater than a first predetermined value and less than a second predetermined value. The low frequency amplitude between the first and second predetermined values is associated with the alpha waves.

Abstract: A focusing circuit for focusing an array of transducers of an ultrasound imaging system includes a variable delay line comprising a plurality of summing amplifiers and a plurality of variable delay elements provided between successive summing amplifiers. A plurality of switches is provided for respectively connecting the transducers to selected summing amplifiers. The amount of delay of each variable delay element is individually controlled so that the corresponding electrical signals derived from the transducers arrive in phase at the output end of the variable delay line.

Abstract: A noise suppressing connector comprises a shielding casing, first and second contact pins to be connected to external circuits, and a filter including at least one capacitor and a coil wound about a core made of a ferromagnetic material. An insulative housing is enclosed by the casing, and this insulative housing has a partition defining a bore with the inner wall of the housing. The first contact pin passes through the partition to project into the bore, while the filter is disposed in the bore to be connected between the first and second contact pins. At least one conductive plate is disposed in the bore and is connected to the casing for effectively shielding the filter and for serving as a ground circuit. The space in the bore may be filled with a suitable insulative material. The number of capacitors and coils may be increased to constitute a desired filter, such as a low-pass, high-pass or band-pass filter.

Abstract: An inner air-tube of a tire for bicycle, particular for racing cycle substantially composed of a thermoplastic urethane resin of a specific type. The urethane resin is comprised of a bifunctional polyol, a diisocyanate and a diol serving as a chain-propagating agent, the ratio by mole of the diisocyanate to a mixture of the bifunctional polyol and the diol being in the range of 1.05-1.10:1. The urethane resin of this type is readily after-crosslinked to improve its physical properties to a great extent.