Abstract: To easily correct the slant of a wire electrode to a workpiece by using the workpiece which is machined into a product and the wire electrode without a special jig. Discharge is generated by approaching a wire electrode 1 to a workpiece fixed on a table. The slant of the wire electrode and correcting amount are calculated by measuring the discharge for a prescribed period of time or a prescribed number of times, while taking the discharge position as a width or a distribution. Then, correction is performed. Therefore, it is possible to correct the slant of the wire electrode relative to the workpiece directly by using the wire electrode. Accordingly, it is possible to drastically reduce the time necessary for getting accuracy in fixing the workpiece on the table and the time necessary for arrangements such as verticality check of the wire electrode by discharge.

Abstract: The metal bond wheel forming apparatus includes rotation speed control means 11 for controlling the rotation speed of a grinding wheel 6; energy control means 9 for controlling discharge energy that is supplied to the gap between a wire electrode 1 and the grinding wheel 6; relative speed control means 17 for controlling a relative movement speed either for the wire electrode 1 or for the grinding wheel 6; and detailed machining control means 23 for controlling the rotation speed control means, the energy control means and the relative speed control means, for setting the rotation speed of the grinding wheel and discharge energy appropriate for detailed machining, and for setting the relative movement speed for the wire electrode or for the grinding wheel to enable high speed shaping during the detailed machining.

Abstract: In an electrical discharge machining apparatus, by adjusting a machining condition changing switch, machining condition changing programs are called from a memory, the machining conditions called from a machining condition group and temporarily memorized in the memory are changed according to the programs, and machining is carried out by machining means according to the machining conditions changed.

Abstract: A semiconductor integrated circuit produces a driving signal for driving a load. The semiconductor integrated circuit includes a compound semiconductor substrate, a logic part including at least a first field effect transistor formed on the compound semiconductor substrate for outputting a first signal, and a driver part including at least a second field effect transistor formed on the compound semiconductor substrate and outputting the first signal through the second field effect transistor as a driving signal. The first field effect transistor is a self-aligned type field effect transistor having a first gate electrode and first and second impurity regions formed in self-alignment to the first gate electrode. The second field effect transistor is a non-self-aligned type field effect transistor having a second gate electrode and third and fourth impurity regions formed in non-self-alignment to the second gate electrode.

Abstract: An electrical discharge machining system is improved by incorporation of an apparatus which permits a machining core to be subdivided into a plurality of sub-cores for separate removal. The invention permits automatic core removal in cases where cores were manually removed in the past, such as where the cores were too large, heavy or irregularly shaped to be handled by the known automatic core disposal apparatus.

Abstract: A method and apparatus of operating a wirecut electrical discharge machine for cutting a workpiece using a generated electrical discharge in a machining gap wherein the workpiece is opposing a wire electrode. The method comprises the steps of presetting a plurality of machining conditions in accordance with dielectric pressure and machined plate thickness combinations, storing the preset machining conditions in a memory, and automatically setting an optimum machining condition based on detected dielectric pressures and the machined plate thickness calculated in a numerical controller. The machined plate thickness may be calculated by dividing an area machining feedrate corresponding to present electrical condition parameters by the actual machining feedrate.

Abstract: The method of preventing a workpiece from being rocked in the machining groove of a workpiece when the wire electrode approaches the final discharge-machining point. As a result, the remaining core can be removed positively and machining accuracy is improved.

Abstract: A wire cut electric discharge machine which is capable of taper-machining with high accuracy. A correction factor which is to correct errors attributing to a special purpose jig is obtained according to a difference between an aimed angle and an actual taper angle of a test workpiece which has been machined with the aimed angle. An automatic correction operation is carried out by using the correction factor to correct the distances of the upper and lower wire guides from a reference table, which have been calculated as necessary for controlling the movement of the wire guides.

Abstract: A core retaining apparatus for a wire-cut electro-discharge machine which is capable of effectively and reliably retaining a core cut out of a workpiece by wire-cut electro-discharge machining when the core is removed to a position outside the machining area. The core retaining apparatus comprises a core retaining element for retaining a core cut out of a workpiece, the element being elastic and having a space therein, and pressure control elements for maintaining the pressure inside the space at a desired value.

Abstract: A pair of guide devices 5, 6 for the wire electrode 1 in a discharge machining apparatus are disposed just above and below a workpiece 3. Each device includes three or more equally circumferentially spaced guide rings 8, 9, 10 surrounding the electrode and biased outwardly by tension springs 11, 12, 13 coupled to an enclosing frame member 7,to thereby center the electrode and prevent any lateral displacements during use. As an alternative the rings may be replaced by guide balls, 22, 23, 24 biased radially inwardly against the electrode by compression springs or fluid cylinders.

Abstract: A compact connection structure between two electrodes made of two types of metals, i.e., metals which respectively make Schottky and ohmic contact with a semiconductor, is provided by using a high melting point metal or silicide thereof which makes Schottky contact with the semiconductor as one electrode metal. The two types of electrodes can be brought into direct contact with each other, enabling elimination of through hole connections between them and therefore increased semiconductor device density.

Abstract: A keyboard type electronic musical instrument wherein tone assignment signals (key depression signals) designated by depressing desired keys of keyboards are transmitted to an electronic circuit block through only one signal line per sort of keyboard as time-divided serial timing signals. The electronic circuit block includes therein a circuit which generates parallel output signals having respectively different timings in correspondence with notes of the keyboards. The parallel timing signals are respectively sent to the corresponding key switches of the keyboards, they are selected by turning "on" the switches, and they are converted by OR circuits into serial timing signals representative of the selected notes. The serial timing signals are sent to a device for detecting and storing notes or chords, whereupon as in prior arts, a tone signal is generated from the obtained signal indicative of a note or chord by tone signal producing device and it is amplified and provided as an output by a loudspeaker.

Abstract: A keyboard type automatic accompanying system wherein information representative of the root note of a chord and the type thereof are detected from key depression signals assigned by depressing a plurality of desired keys of an accompanying keyboard, the detected information are stored, and an automatic chord complying with the particular chord are accompanied. A chord detector comprises in combination a shift register which stores the accompanying key assignment signals therein and which shifts the stored contents cyclically, and a ROM device in which binary information indicative of the basic forms of chord names and the types of chords are stored. Outputs of the shift register are applied to the ROM device, and the type and the root note of the chord are detected in one shift cycle of the shift register, so that the circuit arrangement is simplified, that the detecting time is shortened and that the key response rate is enhanced.