Abstract: A tuning circuit comprises a pair of identical resonant circuits each including a transmission line and a capacitive element, a coupling circuit associated with each transmission line to inject microwave energy into the resonant circuits and extract the tuned energy therefrom. An image trapping circuit is included which comprises a first section which intersects one of the transmission lines and connected to the coupling circuit associated with the intersected transmission line and a second section which extends from the point of connection of the first section with that coupling element to the opposite transmission line in a direction skewed relative to each transmission line. The second section of the image trap circuit provides a smooth interstage coupling between the two transmission lines over a range of resonant frequencies.

Abstract: A tuning device including a conductive housing in which is suspended a dielectric substrate. A pair of first and second resonant circuits is disposed on the substrate in parallel with each other. Each resonant circuit is formed by an elongated conductive film and a capacitive element. An image frequency trapping circuit is arranged to intersect one of the transmission lines to absorb the signal at the image frequency. A grounded conductive strip film is provided adjacent to and parallel with each of the transmission lines and so spaced therefrom that the characteristic impedances of the transmission lines are made equal to each other.

Abstract: By introducing a secondary voltage having a lower frequency than the principal voltage in a grounded transmission line system, detecting the current arising from such secondary voltage only and multiplying such current by the magnitude of the secondary voltage a resultant signal is obtained which is proportional to the inverse of the insulation resistance of the system.

Abstract: There is disclosed a machine tool, of the type having a tool magazine for receiving tools therein, and wherein a spindle head is moved in the direction of the axis of a spindle relative to the tool magazine such that one of the tools in the tool magazine is engaged with or disengaged from the spindle. A draw bar for firmly attaching a tool to the spindle is positioned inside of the spindle. The operation of the draw bar is actuated by the movement of the spindle head relative to the tool magazine.

Abstract: A drilling machine with an automatic tool changer (A.T.C.) including a driving motor which drives a spindle head to traverse, upwards and downwards and a tool magazine which is rotatably supported by the spindle head and has a plurality of tools, wherein when one of the tools is to be interchanged with another of the tools, said tool magazine is rotated at predetermined angles by the driving motor by means of the spindle head and a link mechanism.

Abstract: A drilling machine with an automatic tool changer (A.T.C.) comprising a driving motor for a spindle head and a tool magazine rotatably supported by the spindle head and provided with a plurality of tool arbors for holding tools, one of the tools being interchanged with another of the tools by intermittent rotation of the tool magazine, and wherein the tool arbors are supported for swinging movement between a protrusion position and a retraction position so as not to obstruct the machining operation.

Abstract: The optical resolution of DL-pantolactone is effected by reacting DL-pantolactone or its alkali salt derived therefrom, respectively, with an optically active N-substituted aminophenylpropanol of the general formula: ##STR1## wherein R.sub.1 is a phenyl group which may be substituted and R.sub.2 is an aralkyl group in which the benzene ring may bear a substituent, or its mineral acid addition salt; separating the resulting diastereomers by the aid of difference in their dissolubility; and decomposing them to give the corresponding optical antipodes. This method can provide the antipodes in high purity and yield and can be carried out with ease.

Abstract: A direct positive silver halide photographic emulsion comprising a hydrophilic colloid containing (1) silver halide grains the surface of which is fogged with a sulfur compound and a gold compound, or (2) silver halide grains which are (a) ripened with a sulfur compound and then the surface of which is fogged by optical exposure or (b) ripened with a sulfur compound and a gold compound and then the surface of which is fogged by optical exposure.

Abstract: A vehicle having a hollow body opening at the bottom and adapted to be drawn under suction against the surface over which the vehicle travels. It can travel stably over any surface such as a wall surface, a slope surface or a ceiling surface not to say of a floor surface and can serve a wide variety of purposes including amusements and transportation purposes.