Abstract: The foldable chair in accordance with the invention comprises a front frame 1 having a backrest 12 and a front leg 11, a rear frame 2 projectably holding a slide link 22 which is pivotally mounted to the front frame 1 and provided with a rear leg 21 at its down end, and a seat 3 having its side pivotally supported by the rear frame 2 near its rear end and forward of the pivot position at the rear frame 2 pivotally supported by the front frame 1.

Abstract: A foldable chair 100 comprises a front frame 1 made of pipe material with a backrest 12 provided at its top end and having a pair of front legs 11 continuously extending downward from the top end; a rear frame 2 made of pipe material having a pair of rear legs 21 continuously extending downward from its top end with a sliding shaft whose top end is pivotally mounted to the front frame 1 and whose bottom end is slidably inserted into the top end of each of the rear legs 21; and a seat 3 having its lateral sides pivotally supported near its rear side by the rear frame 2 and by the front frame i forwardly of the position supported by the rear frame 2; and is characterized by that the front frame 1 being provided with concaves 4 formed therein above the seat 3 in use by plastically transforming the pipe material, that each sliding shaft is provided at its upper end with a pivot member 51 mounted to the concave 4, and that the front and rear frames 1, 2 are so arranged that the axis of the rear leg 21 is generally

Abstract: A compact and inexpensive refractory monitoring temperature sensor and a compact and inexpensive refractory erosion location measuring device which can effect continuous detection of erosion over a wide range and specification of a location of an erosion and further can be re-used and used continuously. The temperature sensor includes at least two metal members and an insulating substance (2) filled between the metal members. The sensor detects a condition of an erosion of a refractory not from a melting breakdown of the sensor but from a variation in insulation resistance of the insulating substance which arises from a high temperature of the refractory due to erosion of the refractory. The measuring device incorporates such temperature sensor and discriminates an amount and a location of erosion of the refractory from a variation in insulation resistance between the metal members.

Abstract: A method and apparatus for recording a signal in a magneto-optical disk having pre-pits formed on a recording track which pits are optically detectable for generation of data read and write clocks. The method and apparatus includes the steps of: prior to writing data in the magnetooptical disk, writing a test pattern on a leading portion of a data recording area of the magnetooptical disk at predetermined timings; reading the data recording area to generate a time shift between the read-out test pattern and the original test pattern; adjusting the predetermined timings in accordance with the time shift to generate adjusted data write timings; and writing data in the data writing area in accordance with the adjusted data write timings and the apparatus therefore.

Abstract: An element selecting device for locating one of a plurality of elements on a predetermined plane which comprises a horizontally movable supporting member which supports the plurality of elements on the predetermined plane, wherein the movement of the supporting member is controlled according to the signals of sensors therein. Consequently, by using the element selecting device, in a filter conversion device, for example, the device can be structured simply and reliably with filters of different color separation functions being disposed in a row.

Abstract: A probe for detecting wear of a refractory wall, including plural sheathed probe elements of different lengths each consisting of a pair of high melting point wires disposed in parallel and insulated from each other except at least the fore end portions of the wires which form a normally closed or normally open sensing point, a sheath enclosure accommodating the probe elements such that the sensing points of the respective probe elements are located at different positions along the length of the sheath enclosure and holding the probe elements in parallel relation and out of contact with each other, and a number of dummy elements formed of a material similar to the probe elements and connected to the fore ends thereof in a manner to complement the lengths of the shorter of the probe elements. There is also disclosed a detection circuit for monitoring wear of a refractory wall in a molten metal processing apparatus in a simple and accurate manner by the use of the probe.

Abstract: A method for detecting brazing defects in a plate-fin type heat exchanger with a brazed core structure having a number of wavy fin members alternately with a number of parallelly spaced plate members, in which a pulsed sound in the frequency range of several tens KHz to several hundreds KHz is transmitted across the fin and plate members from a pulser located on one outermost plate member to a sensor located on the other outermost plate member, detecting the positions and sizes of brazing defects two-dimensionally on a plane on the basis of the level of sound received by the sensor. Three-dimensional detection of the position of the defect is also possible by combining therewith a radiographic inspection using a radiant ray source which is located on one lateral side of the core structure to irradiate a radiant ray in a direction substantially parallel with the plate members of the core structure.

Abstract: A thermal sensor for detecting temperature distribution in a deposit layer on the refractory walls of a blast furnace or the like, including a temperature probe assembly having temperature sensing areas at different points along the length thereof, an outer protective casing for accommodating the probe assembly, a number of annular fin members fitted on the temperature sensing areas of the probe assembly and secured to the outer protective casing, and an insulating material filled between the outer protective casing and the probe assembly for thermally insulating the fine members from each other.

Abstract: A method for producing cold rolled titanium strips having good surface quality. The cold rolling of a titanium strip is carried out under the conditions represented by the following formula:X.ltoreq.(48673/Y.sup.1.3283)where X is an average grain size (.mu.m) of the pre-cold rolled titanium strip and Y is a diameter (mm) of the roll for the cold rolling.

Abstract: A method of monitoring the wear of refractor walls of a blast furnace wherein temperature is sensed at different points across the thickness of the furnace walls and various electric representations of the internal phenomena of the blast furnace are derived as trigger signals. Analysis is carried out as to the correlation between the trigger signals and variations in the temperatures at the furnace walls in terms of the time delay, thus predicting the present status of the wear of the furnace walls. A temperature probe assembly is also disclosed which is useful in sensing the temperature distribution of the refractory walls. The temperature probe assembly includes a plurality of parallel sheath type thermocouples or thermometers.

Abstract: In a process for heat treating titanium alloys, and .alpha.+.beta. titanium alloy, heated and held in a temperature range above 500.degree. C. and below the .alpha.+.beta./.beta. transformation point, and then quenched, is further aged at a low temperature in the range between 50.degree. and 300.degree. C.

Abstract: A titanium alloy having a high degree of internal friction and suitable for rotating blades of turbomachines is composed of 5.5 - 6.75% Al, 1 - 5% V, 1 - 5% Mo, V plus Mo being greater than or equal to 5%, and the balance Ti and usual impurities, all by weight. A method of heat-treating the alloy comprises maintaining the same at a temperature not lower than 125.degree. C below its .beta. transformation point for a predetermined period of time and then rapidly cooling the alloy.

Abstract: An induction heating apparatus includes an inverter circuit, a plurality of output coils for induction heating, a coil selection circuit for selectively connecting the output coils to the output terminal of the inverter circuit, and a control circuit for driving the coil selection circuit and inverter circuit so as to cyclically supply the output of the inverter to any selected one of the output coils for each predetermined time of a predetermined cycle. The induction heating apparatus further includes a plurality of output adjusting means for setting the output period of the respective output coils which is included in the predetermined cycle.