摘要:
Proposed is an improved double-layered ceramic heater consisting of an insulating ceramic base plate and two patterned resistance heater element layers formed on both surfaces of the base plate. The improvement comprises forming the patterned heater element layers in such a fashion that the gap space of the heater element layer on one surface, where no heat is evolved by energizing, is opposite face-to-face with the complementary heat-evolving area of the heater element layer on the other surface of the base plate so as to improve uniformity of the temperature distribution over the whole surface of the ceramic heater.
摘要:
There is disclosed a ceramic heater 11 comprising: a plate member 12 made of insulating ceramics in which one or more pair(s) of through-holes 13 are formed; a conductive layer 19 made of conductive ceramics; and a coating layer 21 made of insulating ceramics; wherein a joint member 14 made of conductive ceramics is inserted into the through-hole; an end face 16 of the joint member has a same plane with a main surface 15 of the plate member; the joint member is coated with the conductive layer 19 and thereby fixed to the plate member and also connected with the conductive layer having a heater pattern 20; and an opposite side of the joint member projects from the plate member and the projecting portion 18 constitutes a terminal on which the coating layer is not formed. There can be provided a ceramic heater by which an object to be heated being put directly thereon can be heated uniformly and of which heating efficiency is high and in which the heater main body is not large in size and is compact and scattering of impurities or particles is small and which has a long operating life and is inexpensive.
摘要:
There is disclosed a heating element 10 comprising: a single-piece heat-resistant base member 1 with a plate portion la in which a heater pattern 3a is formed, a rod portion 1b extending from one surface of the plate portion la and in which a current-carrying part 3b is formed, and an end portion 1c at an end of the rod portion 1b on the opposite side of the plate portion la and in which a power-supply terminal 3c is formed; a dielectric layer 2 with insulating property on the surface of the heat-resistant base member 1; a conductive layer 3 with conductive property on the dielectric layer 2, in which the conductive layer 3 is formed as the heater pattern 3a in the plate portion 1a, as the current-carrying part 3b in the rod portion 1b, and as the power-supply terminal 3c in the end portion 1c; and a protection layer 4 with insulating property which covers the surface of the heater pattern 3a and the current-carrying part 3b, in which the dielectric layer 2, the conductive layer 3 and the protection layer 4 are formed to unite with the heat-resistant base member 1. There can be provided a heating element resistant to corrosion of a power-supply terminal, with a long-life protection layer, with high durability, compact in size, and capable of being produced at a low cost.
摘要:
A pyrolytic boron nirtride double container for a source of molecular beams used in molecular beam epitaxy, wherein the transmissivity of an inner container of the pyrolytic boron nitride double container with respect to light having a wave number of 2600 cm−1 to 6500 cm−1 is 90% or less of that of an outer container. The pyrolytic boron nitride double container, which enables molecular beams to generate stably with good temperature controllability and high heat efficiency and which can be used in a stable manner, is provided through a simple process and at low cost, so that molecular beam epitaxial growth can be stabilized, quality of the epitaxial film can be improved, and even though the rise and drop in the temperature of the material melt is repeated, or even at an emergency suspension of the operation, the trouble due to breakage of the container can be prevented.
摘要:
An optical disk includes a plurality of tracks that are arranged in a predetermined number of zones. Each track is divided into a plurality of sectors. The sector number is different in each zone. The sector increases in number moving outwardly on the disk. The optical disk also includes a format marking. The format marking includes a sector field for each sector. The format marking is erasably recorded.
摘要:
An apparatus for recording data includes a source of digital data arranged into data words having a given number of bits and a converter that converts the data words to code words having one more bit than the given number using a group code recording format. The code words include a binary signal having first and second binary values at a given clock interval determined by a bit rate of the code words. The apparatus also includes a storage disk having a recording surface, a drive member for rotatably driving the disk, a laser having a focused beam, and a control assembly for directing the laser at the recording surface so that the beam accesses one of a plurality of concentric tracks on the recording surface. A circuit assembly provides a driving signal utilized for generating energizing pulses having a duration less than the clock interval when the binary signal has the first binary value. A pulse generator applies the energizing pulses to the laser to activate the laser responsive to the energizing pulses so that the laser is turned on and off even when the binary signal does not change value from one bit to the next. A high density optical disk including a plurality of tracks arranged in a predetermined number of zones may be utilized in conjunction the apparatus, which may be further incorporated into an optical data storage and retrieval system.
摘要:
A transportable apparatus for preventing the spreading and coming ashore of spilled oil that is easily transportable to a sea area where spilled oil is spread and that can perform the operation of preventing the spreading and coming ashore of spilled oil in the open area. The apparatus has an oil-fence-housing robot ship (10) and a pair of oil-fence-setting-up robot ships (20, 30) that are separably coupled together into an easily transportable block body. The apparatus encircles a sea area where spilled oil is spread with oil fences (40, 41) by remotely operating the robot ships (10, 20, 30) via radio signals.
摘要:
An apparatus and method for retrieving densely stored data from various types of magnetic media. A medium is scanned to provide an input signal. The input signal is conditioned through differentiation, equalization and partial integration. Positive and negative signal peak detectors are connected to the conditioned signal, and a threshold signal is generating corresponding to an average or midpoint of the measured positive and negative signal peaks. An output signal is generated by comparing the conditioned signal and the threshold signal. The DC component of the input signal is accounted for by feeding back the output signal and adjusting the threshold signal based on the duty cycle of the output signal.
摘要:
A pyrolytic boron nitride crucible is disclosed which is suitable for producing a single crystal of a semiconductor compound of Group III and V by the LEC method. The crucible comprises a side part and a bottom part. The bottom part has an absorption coefficient of light of wavelengths between 3,700 cm.sup.-1 and 6,500 cm.sup.-1 of at most 1.7 and/or the absorption coefficient of light of wavelengths between 3,700 cm.sup.-1 to 6,500 cm.sup.-1 of the bottom part is less than that of the side part by at least 0.5. In the crucible, the heat conduction from the bottom part to material melt in the crucible is strengthened, so that the convection flow of the material melt is suppressed and the temperature distribution in the crucible can be easily controlled.
摘要:
Proposed is an article of pyrolytic boron nitride such as crucibles for use at a high temperature under an extremely high vacuum as in the molecular beam epitaxy. The article can be used in the high temperature, high vacuum process without the conventional elaborate and time-consuming degassing bake-out treatment because the article is wrapped in a wrapping film having a specified low moisture permeability immediately after a preliminary degassing treatment under specified conditions before the article is wrapped under a low-moisture atmosphere in a glove box.