摘要:
The threaded joint for tubes according to the invention concerns sealed end to end connections of metal tubes useable in particular in the petroleum industry. This joint comprises a sleeve provided with two housings with tapered threads into which are screwed the male extremities of two metal tubes provided with corresponding threads having non-threaded extremity zones the front walls of which abut one against the other, a clearance existing between the lateral walls of these zones and the annular wall of he sleeve opposite. Two pairs of male/female shoulder stops prevent over-screwing. The heights of the teeth of the male and female threads are identical.
摘要:
A method and apparatus for burning a liquid fuel by introducing gas into the liquid fuel through capillaries, a porous plate, cloth, a particle layer or the like to bubble the liquid fuel to control the fuel level and simultaneously by supplying combustion air separately to accomplish complete combustion.
摘要:
An electrostatic discharge protection circuit is provided with a variable threshold for limiting the potential of an input signal having a given high or low voltage, and is adapted to an EPROM containing an input MOS transistor which is responsive to the input signal. The protection circuit is associated with an input terminal for receiving the input signal. The input terminal is coupled to the gate of the input MOS transistor. The protection circuit also includes a circuit element for limiting or suppressing the input signal potential at the variable threshold. The gate of the input MOS transistor receives the potential limited signal from the circuit element. The circuit element is responsive to a given threshold control potential. The variable threshold is enhanced by the given threshold control potential when a high-voltage input signal is applied to the input terminal.
摘要:
A threaded joint for an oil well pipe having (1) a tapered threaded having roughly the shape of a buttress thread, (2) a pin having a male thread and a box having a female thread, (3) a seal and a torque shoulder, characterized in that (i) the load flank angle of the threads is -20.degree. or greater and less than 0.degree., the stab flank angle is greater than 30.degree. and at most 60.degree. (ii) there is a positive amount of interference between the male threads and the female threads, and (iii) during and at the completion of make-up, the load flanks and the stab flanks are contacting each other, and there is a gap between the crests and the roots.
摘要:
A semiconductor integrated circuit which has a CMOS inverter formed of p- and n-channel MOSFETs, and a D-type n-channel MOSFET coupled at the gate to the output terminal of the CMOS inverter, having one end coupled to a high voltage terminal and the other end coupled to the drain of the p-channel MOSFET.
摘要:
A thread joint for a tube which suppresses galling without deteriorating its sealing performance since a sliding distance L.sub.S which expresses a quantity of spiral sliding of sealing portions relative to each other during a tightening period from the start of a contact between the sealing portions until shoulder portions abut each other satisfies the following relationship:Sliding Distance L.sub.S .ltoreq.-0.0093.times. (Tube Outer Diameter).sup.2 +4.73.times. (Tube Outer Diameter).To shorten the sliding distance L.sub.S, the sealing portion of a box portion is formed shorter than the sealing portion of a pin portion. In this case, a circumferential groove may be formed to discharge a dope. Conversely, the sealing portion of the pin portion is formed shorter than the sealing portion of the box portion. In this case, a precedent-stage unthread portion whose inclination is smaller than that of the sealing portion of the pin portion is formed between a male thread and the sealing portion of the pin portion. In addition, tapers of the sealing portions of the pin portion and the box portion are set at 1/6 or larger, and/or, a distance where the sealing portion of the box portion (pin portion) is formed so as to contact a curve which is tangent to the sealing portion of the pin portion (box portion) is 1.45 mm or larger.
摘要:
A semiconductor integrated circuit which is protected from element breakdown includes a memory cell, series-connected first and second program load transistors arranged between the memory cell and the program power source, a boosting circuit for outputting a board voltage higher than the voltage of a program power source, and a controller. The controller applies the boosted voltage to the gates of the first and second program load transistors when program data is set at a first logic level. The controller applies a voltage of about 0 V to the gate of the first program load transistor and an intermediate voltage lower than the voltage of the program power source and higher than 0 V to the gate of the second load transistor when the program data is set at a second logic level.
摘要:
A sub-booster circuit for further stepping up an output voltage of a main booster circuit includes a first MOS transistor having a drain connected to the output terminal of the main booster circuit, and a gate connected to an input terminal of an object circuit, a second MOS transistor having a drain and a gate connected to the source of the first MOS transistor and a source connected to the input terminal of the object circuit, and a MOS capacitor having a first electrode connected to a connection node between the first and second MOS transistors and a second electrode connected to receive a clock pulse signal. A threshold voltage of the second MOS transistor is set to be larger in its absolute value than a threshold voltage of the first MOS transistor and the MOS capacitor has substantially the same threshold voltage as that of the second MOS transistor.
摘要:
A control pulse generator according to the present invention includes a voltage generator for generating an output voltage proportional to a power supply voltage, an inverter for generating an inversion signal whose signal level is inverted when the output voltage from the voltage generator reaches a predetermined value, and a pulse signal generator for delaying a level inversion timing of the inversion signal by a predetermined delay time, and generating a control pulse having a width corresponding to the delay time. According to the control pulse generator with the above arrangement, the width of the control pulse can be determined on the basis of the delay time of the pulse signal generator, regardless of rise states of the power supply voltage. In addition, the height of the control pulse can be set at a desired value according to a supply voltage to the pulse signal generator, regardless of rise states of the supply voltage.
摘要:
In an electrically-erasable/programmable nonvolatile semiconductor memory device according to the invention, a one-bit memory cell is constituted by a series circuit of a selecting MOS transistor and a data storage MOS transistor. A floating gate electrode and a control gate electrode are formed in the data storage MOS transistor, One portion of the floating gate electrode is formed on a channel region of the data storage MOS transistor through a gate insulating film. The other portion of the floating gate electrode is formed on a drain region of the data storage MOS transistor through a gate insulating film, a portion of which is sufficiently thinner than the gate insulating film. One and the other portions of the floating gate electrode are structurally separated from each other but are electrically connected with each other on a field region. A control gate electrode having substantially the same shape as that of the floating gate electrode is formed thereon through a gate insulating film.