Abstract: An anti-adhesion material comprising decellularized tissues and a biocompatible polymer or fibrin glue; a method for preparing an anti-adhesion material comprising complexing a biocompatible polymer or fibrin glue to decellularized tissues; an anti-adhesion material kit comprising decellularized tissues and a biocompatible polymer or fibrin glue; a substitute biomembrane comprising decellularized tissues and a biocompatible polymer or fibrin glue; a method for preparing a substitute biomembrane comprising complexing a biocompatible polymer or fibrin glue to decellularized tissues; and a substitute biomembrane kit comprising decellularized tissues and a biocompatible polymer or fibrin glue.

Abstract: A method of producing a decellularized transplantation material, wherein the method includes the steps of (a) harvesting a branch-bearing blood vessel from a vertebrate animal (a donor); (b) decellularizing the blood vessel; and (c) adhering, by a protein denaturation treatment, a portion where a branch has been excised to close the vessel. Also, a graft composition consisting of a biocompatible material that contains the decellularized transplantation material.

Abstract: An anti-adhesion material comprising decellularized tissues and a biocompatible polymer or fibrin glue; a method for preparing an anti-adhesion material comprising complexing a biocompatible polymer or fibrin glue to decellularized tissues; an anti-adhesion material kit comprising decellularized tissues and a biocompatible polymer or fibrin glue; a substitute biomembrane comprising decellularized tissues and a biocompatible polymer or fibrin glue; a method for preparing a substitute biomembrane comprising complexing a biocompatible polymer or fibrin glue to decellularized tissues; and a substitute biomembrane kit comprising decellularized tissues and a biocompatible polymer or fibrin glue.

Abstract: A wire temperature measuring method for a wire electric discharge machine, by which temperature and temperature distribution of a wire can be accurately measured during electric discharge machining. After a machining voltage is cut off, a loop current flows. Based on the loop current and a voltage between electrodes measured by a differential amplifier, a resistance between the electrodes is obtained, and the temperature of a wire is obtained based on the resistance. Accordingly, the wire temperature during actual machining operation can be measured with accuracy.

Abstract: A wire temperature measuring method for a wire electric discharge machine by which temperature and temperature distribution of a wire can be accurately measured during electric discharge machining. After a machining voltage is cut off, a loop current flows. Based on the loop current and a voltage between electrodes measured by a differential amplifier, a resistance between the electrodes is obtained, and the temperature of a wire is obtained based on the resistance. Accordingly, the wire temperature during actual machining operation can be measured with accuracy.

Abstract: A gap voltage detector in a wire-cut electric discharge machine is provided, which is capable of eliminating an adverse effect due to a variation in an electric discharge position, thereby detecting a gap voltage between a wire electrode and a workpiece in an accurate manner.

Abstract: An initial hole machining device for a wire-cut electric discharge machine, which is capable of efficiently performing initial hole machining over the entire electric discharge machinable region determined by the mechanical structure of the electric discharge machine, without the need of shifting a machine coordinate system or correcting position command data and of providing a separate machining liquid feed device. The initial hole machining device has a body removably fitted in a nozzle hole of an upper wire guide of the electric discharge machine for movement between an initial hole machining position where it is fitted in the nozzle hole and a set-aside position where it is spaced from the upper wire guide. A pipe electrode for initial hole machining is mounted to the body coaxially with a wire electrode.

Abstract: A working-condition detecting method for a wire electric discharge machine and an apparatus therefor are provided, for positively and experimentally determining a working condition for optimum and most efficient wire electric discharge machining. Test machining is carried out while gradually increasing off-time of a transistor of a discharge power source of the machine every predetermined working section. Unfulfillment of a linear relationship between an average working electric current and a working speed is determined when a ratio of an increment of the working speed with respect to that of the average working electric current between the preceding and present working sections becomes smaller than a value, equal to the product of a coefficient and an average value of the ratios in the entire working sections until this time and smaller than the average value. The off-time at this time is identified as the working condition which is used to carry out actual machining.

Abstract: An electric-discharge-machining power source in an electric discharge machine, which is capable of generating machining pulses each having a large peak value and a small pulse width, thereby attaining an improved machining speed. In the electric-discharge-machining power source, when supply of a power source voltage in between a workpiece (W) and a tool electrode (P) is prohibited by transistors (T1, T2), a generated return current attributable to energy accumulated in stray inductances (L1, L2) is returned to a high-voltage smoothing capacitor (C2) through return diodes (D1, D2). This allows the capacitor to be charged up to a voltage exceeding the power source voltage. As a result, the return current falls rapidly. In response to an output from a comparator (1) generated when a divided voltage (VH) corresponding to the capacitor charge voltage exceeds a reference voltage (VL), a transistor (T3) is rendered to be conductive.

Abstract: An electric discharge position detecting device of a wire electric discharge machine which is capable of accurately detecting an electric discharge position with use of a relatively simple arrangement. In a divider (13), an output voltage from a differential amplifier (11), corresponding to the difference between output voltages of coils (9, 10), indicative of the differentials of discharge currents flowing individually through upper and lower conductors (4, 5), is divided by an output voltage of an adder (13), indicative of the differential of the total discharge current, and a voltage indicative of the electric discharge position is delivered from the divider. Each time a machining pulse from an electric discharge machining power source (3) is applied to a machining gap, the divider output is sampled and held, and is then compared to the respective reference voltages of comparators (C1 to C3).

Abstract: An electrical discharge machining apparatus compensates for an inductance fall component and a resistance fall component in a sensed machining gap voltage. The inductance fall component is determined by a current variation rate sensed by an instrument current transformer. The resistance fall component is sensed by a resistor, an integrator, or a combination of a second instrument current transformer and an ingegrator. The sensed gap voltage is then compensated for the resistance fall component and the inductance fall component.

Abstract: An electric discharge machining control apparatus is provided capable of effecting straight machining, corner machining, and arcuate machining in a stable manner, with improved accuracy. A numerical control unit serves for straight machining under optimum electrical conditions, and controls the on-off operation of relay contacts to and the on-off duty ratio of a pulse oscillator, in order to establish the respective optimum values of a capacitor charging voltage, discharge current, and charge and discharge time read out from a memory in accordance with a calculated corner angle or a calculated radius of a circular arc, machining.

Abstract: An electric discharge machining power source is provided which charges a capacitor connected in parallel with an electrode and a work, and applies a charge voltage between the electrode and the work to cause electric discharge, thereby performing electric discharge machining. The machining power source allows rapid charging of the capacitor and is inexpensive while the power source efficiency is improved. A switching element is arranged in the charge circuit of the capacitor which is capable of being turned on and off. The switching element connects the capacitor to a direct current power source and charges the capacitor. A flywheel circuit including an inductance and a diode is provided in the charge circuit. A reverse voltage that is caused by a stray inductance in the electric discharge circuit during electric discharge is applied to the capacitor as a positive voltage through the flywheel circuit.

Abstract: An electric discharge apparatus in which a voltage is applied between a workpiece and a wire and a machining liquid is supplied into a gap between the workpiece and the wire for machining the workpiece. When a nozzle cannot be located closely to the surface of the workpiece, a nozzle liquid pressure is calculated from the nozzle height, and reference machining conditions are varied by the nozzle liquid pressure, so that optimum machining conditions can automatically be determined. Machining conditions (the Material M, the workpiece thickness t, the wire diameter d) are entered from an input means (1), and reference machining conditions (Vo, Ton0, Toff0) from a machining condition storing means (3) for the electric discharge wire cutting apparatus are selected. Nozzle liquid pressures (Pu, P1) are calculated by a calculating means (2) from nozzle heights (u, 1) entered from the input means (1).

Abstract: An electric discharge machining control apparatus which controls an electric discharge machining power source of a wire electric discharge machine in accordance with a leakage current flowing between a wire electrode (2) and a workpiece (3). This permits stable electric discharge and satisfactory surface roughening. The control apparatus described above, the peak value of a machining voltage applied between the wire electrode (2) and the workpiece (3) is detected by means of a peak voltage detecting circuit (D4, R8, R9, C2). When the leakage current increases so that a detection value is reduced, the on and off times of switching elements (Tr1, Tr2), interposed between a DC power source (1) and the wire electrode and between the DC power source and the workpiece, are changed from a value smaller than the time constant (R1.C1) of a charge and discharge circuit to a value larger than the time constant. Thus, the machining voltage increases.

Abstract: A position finding apparatus of an electric discharge machine has a switching device including a relay 3 set into operation when tool electrode position finding starts, so that the switching device turns off machining power applied across a workpiece W and a tool electrode P. At such time, a differentiated waveform, which is obtained by differentiating in a differentiating circuit 15, a square wave produced by a pulse oscillator, is applied across the workpiece W and tool electrode P. Thereafter, position finding is performed with regard to the tool electrode P. A resistor in the differentiating circuit 15 can be made variable in value to alter the differentiated waveform applied across the workpiece W and tool electrode P.

Abstract: An automatic wire connecting apparatus of a wire cut electric discharge machine performs automatic connection of a wire electrode smoothly and reliably. A wire processing unit (90) integrally rotatably coupled to a rotating shaft (61) of a pneumatic motor (60) has a nozzle forming portion (12) which defines a slit (S) that allows a wire electrode (W) to pass therethrough when it is opened, and which defines a nozzle hole (125) capable of fitting with an upper wire guide (12) when it is closed, and is selectively positioned at a wire insertion position or an escape position by a rotary stopper (150). When the wire electrode is broken, the wire processing unit is rotated from the escape position to the wire insertion position by a motor, and thereafter, the nozzle hole forming portion is closed, thereby holding the wire electrode guided through the slit during a rotating operation in the nozzle hole.

Abstract: A wire cut electric discharge machine for electric discharge machining a work (W) held on a work table (24). A wire electrode (14) supplied by a wire supplying device (12) is passed between upper and lower heads (22, 26) under tension through an electric discharge machining region where the work (W) is subjected to electric discharge machining.

Abstract: A method for wire electrode type electrical discharge machining and equipment employable therefor realize high accuracy in corner machining, such machining being conducted in combination with taper machining. The tension to be applied to a wire electrode is controlled in proportion to a change in Young's modulus of the wire electrode in addition to decreasing the machining current, whenever a corner machining and a taper machining are conducted in combination. The equipment for wire electrode type electrical discharge machining includes a memory for memorizing information indicating the relationship between the machining current and the amount of tension which is optimum to the machining current, a monitor for monitoring the electric discharge machining current, an optimum tension calculating device for calculating the tension optimum to the monitored machining current, and a tension control device for controlling the tension of the wire electrode in response to the calculated optimum tension.

Abstract: A wire guide for wire electrode type electrical discharge machining be employed both for taper machining and for non-taper machining with high accuracy, regardless of the magnitude of the taper angle. The guide can be readily connected to (threaded with) a wire electrode and can be employed in an electrical discharge machining apparatus having an automatic wire connecting (threading) system. The wire guide is provided an arc-shaped guide arranged at a location concentric with a wire electrode for electrical discharge machining, a three-point-supporting guide arranged closely to the arc-shaped guide along the wire electrode for allowing the wire electrode to pass therethrough, and an external tube member for holding the arc-shaped guide and the three-point-supporting guide therein. The guide has a center hole for allowing the wire electrode to pass therethrough and a cooling liquid supply hole for supplying a cooling liquid for cooling the wire electrode.