Abstract: A communication system comprising a plurality of devices interconnected into a loop and each provided with two pairs of sending and receiving terminals for transmitting signals in directions different from each other. Each of the devices is connected to the other devices immediately adjacent thereto on the loop by a pair of transmission channels connected to the two pairs of sending and receiving terminals and each including a sending line and a receiving line. Each device comprises a first arrival preference circuit which disciminates whether a first or second input terminal receives a signal first. Also, a control circuit causes the terminal which receives the first arrived signal to accept that signal while the other terminal is inhibited from accepting any signals. A predetermined one of the terminals is controlled to accept an input signal when input signals arrive at the two terminals simultaneously.

Abstract: A production process control system comprising a plurality of terminal devices and a central device connected to the terminal devices, each of the terminal devices at least including means for counting the amount of work done (i.e. output), means for entering a worker identifying code and means for transmitting the counted output and the entered worker identifying code to the central device, the central device at least having means for performing communications with each terminal device and means for storing the output and the worker identifying code transmitted from the terminal device as associated with each other.

Abstract: A sewing machine for sewing together two sheets of material and for separating and pressing their edges, includes folding means for separating and folding the edges and an ultrasonic generator for pressing and creasing them. An additional device includes a speed sensor for sensing a sewing speed of the sewing machine and a control device for controlling the ultrasonic generator to vary a strength of the ultrasonic wave according to the sensed sewing speed.

Abstract: A catalytic structure for cleaning exhaust gas from automobiles, etc., is provided. The catalytic structure comprises a ceramic carrier having a three-dimensional network skeleton forming the intercommunicating voids therein and a catalyst-carried activated alumina layer formed on the surface of the three-dimensional network skeleton. This catalytic structure is produced by contacting a ceramic carrier with a catalyst-containing solution and drying the carrier by evaporating the solvent in the solution so that the catalyst will be carried at a higher density in the activated alumina layer on the side of the skeleton surface against which side the incoming exhaust gas does not impinge, than on the side against which the exhaust gas impinges.

Abstract: A method of applying .gamma.-alumina to a porous ceramics structure includes the steps of: causing fine particles of .gamma.-alumina together with a carrier gas to flow through pores in the porous ceramics structure so as to deposit the .gamma.-alumina fine particles on the surfaces of the skeleton of the porous ceramics structure, and heating the structure with the .gamma.-aluminum particles deposited thereto to a predetermined temperature thereby fixing the .gamma.-alumina particles. The fine particles of .gamma.-alumina are formed by causing an arc discharge between the surface of molten aluminum and an aluminum electrode so as to generate vapor of aluminum, and oxidizing the aluminum vapor by an oxidizing gas which may be Ar-O.sub.2 carrier gas which is made to flow through the pores in the porous ceramics structure.

Abstract: A circuit interrupter includes an arc extinction assembly for magnetically driving or blowing out an arc formed between a stationary contact and a movable contact. The assembly comprises a pair of coaxial windings which are disposed in proximity to the contacts so that the internal lines of magnetic force generated by and passing inside of the windings can act directly on the arc for magnetically driving the arc in one direction. A magnetic flux diverting yoke is provided in association with the windings to diverse therethrough the external lines of magnetic force generated by and passing outside of the windings such that the arc and a portion of the movable contact arm carrying the same will not be under the influence of the external lines of magnetic force even when the contact separation proceeds to a stage where the arc is extended past the region which is totally under the influence of the internal lines of magnetic force.

Abstract: A circuit breaker capable of breaking an associated circuit when an overcurrent higher than a rated current keeps flowing through the breaker or upon a short-circuit current. Electric power path in the breaker is partly inserted through an arm of a magnetic material and holding a movable contactor plate of make-and-break contact means, an armature means is provided as pivoted at one end to the holding arm, and a tension spring means is provided between the other end of the armature means and the movable contactor plate to provide a contact pressure. The overcurrent flowing through the path causes a magnetic force to be induced in the holding arm, whereby the armature means is rotated to change the direction in which the force of the tension spring means acts on the movable contactor plate and the latter breaks the contact means.