Abstract: In a communication control system for an air conditioner including an outdoor unit, plural indoor units and control equipment such as a remote controller, etc. which is connected to each indoor unit through a communication line, data communication being carried out between each indoor unit and the control equipment through the communication line, each indoor unit is equipped with a communication control device having a power source circuit 59 to which a power source voltage is supplied from a main power source, a communication superposing circuit for superposing communication data on the power source voltage, a transistor 54 for ON/OFF-controlling the supply of the power source voltage from the main power source to the communication superposing circuit, and a polarity coincidence circuit 63A that passes the output of the communication superposing circuit therethrough to the communication line and depolarizes the power source voltage from the external.

Abstract: A Zn or part-Zn plated steel sheet has an MgO coating free of metallic Mg thereon which increases corrosion resistance and plating adherence. The MgO coating is formed by coating according to the sol-gel method or by dipping or treating by cathodic electrolysis a Zn or part-Zn plated steel sheet in a molten salt bath mainly containing a magnesium salt.

Abstract: In a machine tool provided with a column 4 mounted on a back end portion of a bed 1 having a table 2, and a spindle head 20 arranged in a vertically movable manner to the column 4, both sides of an upper portion of the column 4 is connected with both sides of a front-end portion of the bed 1 through support members 42, 43. Even the machine has a structure that the spindle head 20 embeds a main shaft rotating at high rpm, vibration can be reduced. The column is affected by a force to fall down in the direction due to the weight of the spindle head 20, but the tilt caused by the force can be avoided. Accordingly, a high finish surface accuracy can be ensured without an increase in size and weight.

Abstract: A process for the manufacture of tinplates comprising electroplating a substrate in a fused-chloride tin plating bath at a temperature of about 150.degree. to 350.degree. C., a current density of about 100 to 500 A/dm.sup.2 in an atmosphere of a non-oxidizing gas. This process may be converted to a process for the manufacture of reflow type tinplates by only changing the bath temperature, and vice versa. For the manufacture of no-reflow type tinplates, the bath is kept at 150.degree. to 232.degree. C., while for the manufacture of reflow type tinplates, the bath is kept at 233.degree. to 350.degree. C. In these cases, the bath includes SnCl.sub.2 and at least one member selected from the group consisting of KCl, NaCl, LiCl and AlCl.sub.3, and may preferably be operated while flowing the bath at a flow rate of about 0.1 m/sec higher.

Abstract: A plated steel sheet is produced by an electroplating in a plating bath of about 350.degree. to 500.degree. C. containing a chloride of Zn, a chloride of Mg and one, two or more of chlorides of Na, K and Li, with a plating current density ranging between about 20 and 350 A/dm.sup.2.The Zn-Mg alloy plated steel sheet superior both in plating adhesion and corrosion resistance has a plating layer formed on at least one surface thereof in an amount of about 10 to 60 g/m.sup.2, and by electroplating in a bath of a fused salts, the plating layer containing about 1 to 35 wt % of Mg, about 0.5 to 25 wt % of mean value of Fe and the balance substantially Zn and incidental inclusions. The Fe content in the plating layer has such a gradient that its concentration is greatest at the interface between the plating layer and the steel sheet and progressively decreases towards the surface of the plating layer opposite to the steel sheet where the Fe content is substantially zero.

Abstract: There are provided a pair of concentric inner and outer annular magazines each provided with a plurality of tool pots and a blind pot which are arranged along a circle, and magazine driving device for independently rotating the outer and inner magazines to bring a tool pot containing a designated or the blind pot to predetermined tool pot indexing positions, and a tool holding pot disposed on the outside of the outer annular magazine for temporarily holding a tool taken out from one of the tool pots of the inner or outer magazine or a tool returned from a machine tool. The center of the holding pot lies on a line interconnecting the center of the inner and outer magazines and the tool pot indexing positions thereof. A saddle including a tool transfer arm with a tool gripper is moved along the line for inserting and taking out a tool into and out of a designated tool pot, and a tool exchanging mechanism is used to exchange a tool between the tool holding pot and the machine tool.