摘要:
The invention provides damping techniques for a rotating shaft. The rotating shaft is supported by rotary bearings. The damping techniques control vibration of the rotating shaft by creating a fluid film in a support element of the rotating shaft. For example, the fluid film may be created between a housing and the rotary bearings. The fluid may be supplied by a pump, and the supply amount of fluid to create the fluid film is relative to the rotational velocity of the shaft. Vibration can be prevented for every operational rotational velocity of the rotating shaft. In some embodiments, the rotating shaft may be powered by or part of an electric motor for a vehicle.
摘要:
A drive unit is provided for driving a wheel installed on a vehicle. The drive unit includes a driving source equipped with a rotary shaft. A speed reducer is connected between the driving source and the wheel so as to reduce the rotational speed of the rotary shaft and transmit the reduced rotational speed to the wheel. A brake unit is provided having a rotary member rotationally connected to the speed reducer on a side of the speed reducer opposite from the wheel so as to brake the rotation of the wheel through the speed reducer.
摘要:
A defect detection method and system which can provide a precise determination of whether an object is acceptable without being affected by the position of placement and the rotational orientation of the object. An arc circumscribing the tip of modules of a sprocket is determined. Then, each overlapping region is extracted which is formed by an overlapping portion between an inner portion of a region defined by the arc and the cut-away portion of the sprocket. The area of each overlapping region is determined and compared with each other. In accordance with a determination of whether each area difference falls within the predetermined range of criteria &egr;, it is determined whether a chipped portion exists on the tip of module. If there is a chipped portion on the tip of module, two or more overlapping regions are integrated with each other to form a larger overlapping region, thereby making it possible to determine easily and positively the presence of a chipped portion on the tip of module.
摘要:
The disclosed method of measuring the flow of a fluid with a porous particulate ceramic tracer and an optical instrument is characterized in that spherical particles having diameters in the range of 0.5 to 150 .mu.m are used as the tracer. Inasmuch as the tracer particles for flow measurement are spherical, the sectional area of scattered light to be detected by an optical sensor means is constant regardless of the orientation of particles. Furthermore, spherical particles have no surface irregularities that might cause concatenation so that individual particles are not agglomerated in tracking a fluid flow, thus contributing to improved measurement accuracy.
摘要:
A fuel assembly has part length and full length fuel rods, and a pair of large-diameter water rods which occupy an area which can accommodate 7 fuel rods. Natural uranium regions are provided in the upper and lower end portions of the effective fuel zone of the fuel assembly. An intermediate region between these upper and lower natural uranium regions provides an enriched uranium region which has three axial sections: an upper section, a middle section and a lower section. The middle section has the highest average enrichment, the lower section has the medium average enrichment and the upper section has the smallest average enrichment. The difference in the average enrichment between the middle section and the lower section is smaller than that between the middle section and the upper section. The upper section has a lower concentration of burnable poison than other sections of the enriched uranium region. According to this arrangement, a greater burn-up degree of the fuel assembly can be achieved with minimal increment of the average enrichment, while preserving sufficiently large safety margin such as the thermal margin of the reactor and the reactor cold shut down margin.
摘要:
A fuel assembly for a boiling water reactor comprising an upper and lower tie plates, a plurality of fuel rods filled therein with a plurality of fuel pellets, a fuel bundle comprising the fuel rods retained with a plurality of spacers in spaced relation and disposed between the upper and lower tie plates, and a polygonal tube-like channel box which encloses the fuel bundle and constitutes flow paths for coolant. The fuel rods comprise long fuel rods and short fuel rods which are each shorter in the effective portion than each of the long fuel rods. The concentration of fissile material in each of the short fuel rods is lower than the mean concentration of fissile material in the cross section of the fuel bundle. In the case the fuel bundle is vertically subdivided into two regions, an upper and lower one, with the upper end of the effective portion of each of the short fuel rods as a border, the mean concentration of fissile material in the cross section of the fuel bundle in the region lower than the border is lower than that in the cross section of the fuel bundle in the region above the border.
摘要:
A period of a correlation signal from a laser Doppler velocimeter is calculated from crossing points at which a correlation function crosses over a threshold level by clipping and digitizing a Doppler burst signal, thereby enabling an accurate and real time measurement to be made of a flow velocity, even in low SNR Doppler signals. Smoothing the waveform of a correlation signal further improves measurement accuracy. When the threshold level is set to be the 1/2 value of the autocorrelation function at .tau.=0, a crossing point is precisely detected even in an uneven correlation function or small amplitude of the crosscorrelation function, thus further increasing measurement accuracy.
摘要:
A novel ternary intercalation compound of a graphite with a metal fluoride and fluorine, which is represented by the formula C.sub.x F(MF.sub.z).sub.y wherein M is Al or Mg and z is an integer corresponding to the valence of M, is produced by contacting a graphite material with a metal fluoride selected from AlF.sub.3 and MgF.sub.2 in an atmosphere of fluorine gas at a temperature of 0.degree. C. to 400.degree. C. for at least a period of time to effect a weight increase in the graphite. The ternary graphite intercalation compound thus obtained has not only an excellent stability to humidity or moisture but also a high electrical conductivity. The novel ternary graphite intercalation compound according to the present invention may be practically used as a novel electrically conductive material and a catalyst of organic reactions.
摘要:
The invention provides a rubber composition for golf balls which includes (A) a base rubber containing a polybutadiene having a cis-1,4 bond content of at least 60 wt %, (B) an unsaturated carboxylic acid and/or a metal salt thereof, and (C) a diphenylamine of the general formula wherein R1 and R2 are each independently a hydrogen atom or a hydrocarbon group of 1 to 20 carbons, m is an integer from 1 to 5, and n is an integer from 1 to 4, with the proviso that if m and/or n is 2 or more, each occurrence of R1 and R2 may be the same or different. The golf ball rubber composition of the invention enables a high-quality molded and crosslinked product having a suitable hardness and a high resilience to be obtained.
摘要:
The disclosed method of measuring the flow of a fluid with a porous particulate ceramic tracer and an optical instrument is characterized in that spherical particles having diameters in the range of 0.5 to 150 μm are used as the tracer. Inasmuch as the tracer particles for flow measurement are spherical, the sectional area of scattered light to be detected by an optical sensor means is constant regardless of the orientation of particles. Furthermore, spherical particles have no surface irregularities that might cause concatenation so that individual particles are not agglomerated in tracking a fluid flow, thus contributing to improved measurement accuracy.