Abstract: A wire electrical discharge machine which performs electrical discharge machining on a workpiece, includes: a worktable on which the workpiece is placed; a placement area detector that divides the top surface of the worktable into multiple areas and detects the areas where the workpiece is placed; a placement time measuring unit that measures placement time for which the workpiece is placed on each of the areas detected by the placement area detector; and a cumulative time storage that adds up the placement times measured by the placement time measuring unit for each of the areas as a cumulative time for the area.

Abstract: A wire electric discharge machine has a function of estimating the time for replacement of a filter based on a use situation for the machine. A time Tr during which the filter is serviceable is calculated according to an equation, Tr=|(Pd?Pn)/?P|, based on a fluid pressure variation amount ?P, a current filter fluid pressure Pn, and a filter life pressure. A remaining available time Td for the filter which takes into account the operation rate of the machine is calculated according to an equation, Td=Tr/W.

Abstract: A wire electrical discharge machine which performs electrical discharge machining on a workpiece, includes: a worktable on which the workpiece is placed; a placement area detector that divides the top surface of the worktable into multiple areas and detects the areas where the workpiece is placed; a placement time measuring unit that measures placement time for which the workpiece is placed on each of the areas detected by the placement area detector; and a cumulative time storage that adds up the placement times measured by the placement time measuring unit for each of the areas as a cumulative time for the area.

Abstract: A wire electric discharge machine according to invention prevents occurrence of failure beforehand and prevents machining stop. This can be effected by acquiring an image of a part using an image information collection unit such as a visual sensor with respect to matters, which requires inspection management of the amount of a wire accumulated in a wire electrode storage box, a remaining amount of a wire of a wire bobbin, a level of a machining liquid of a water reservoir and the like, and issuing warning when it is determined, based on the obtained image information, that the failure is highly likely to occur as the wire deposition amount is close to a limit of the wire electrode storage box, the wire remaining amount is small, or the machining liquid level falls below a set value to deal with the state based on this warning.

Abstract: One arbitrary point on an upper surface of a workpiece and two points at arbitrary heights on a tapered section of the workpiece are measured using a contact detector disposed on an upper wire guide of a wire electric discharge machine to calculate the shape accuracy and tapered angle. Based on the calculated data, the upper and lower wire guide support positions of the upper and lower wire guides are calculated. Using the calculated upper and lower wire guide support positions, electric discharge machining is performed on the workpiece.

Abstract: A wire electric discharge machine has a function of estimating the time for replacement of a filter based on a use situation for the machine. A time Tr during which the filter is serviceable is calculated according to an equation, Tr=|(Pd?Pn)/?P|, based on a fluid pressure variation amount ?P, a current filter fluid pressure Pn, and a filter life pressure. A remaining available time Td for the filter which takes into account the operation rate of the machine is calculated according to an equation, Td=Tr/W.

Abstract: When contact between a wire electrode and a workpiece is detected while, after wire electric discharge machining is ended, the wire electrode is moved (retraced) in the direction opposite to the machining direction along the machining path, the movement of the wire electrode is stopped. The wire electrode is moved in the offset direction from the contact position. When the wire electrode and the workpiece are brought into a non-contact state, the non-contact state is detected, and the movement of the wire electrode is stopped. The wire electrode is returned from the non-contact position to the machining path, and the wire electrode is retraced along the machining path in the state where the detection of contact between the wire electrode and the workpiece is neglected. Then, an amount of distortion of the workpiece is calculated from the contact position and the non-contact position.

Abstract: One arbitrary point on an upper surface of a workpiece and two points at arbitrary heights on a tapered section of the workpiece are measured using a contact detector disposed on an upper wire guide of a wire electric discharge machine to calculate the shape accuracy and tapered angle. Based on the calculated data, the upper and lower wire guide support positions of the upper and lower wire guides are calculated. Using the calculated upper and lower wire guide support positions, electric discharge machining is performed on the workpiece.

Abstract: The present invention relates to a releasable aqueous coating composition containing (A) a resin dispersion containing a carbonyl group-containing copolymer aqueous dispersion and a polyhydrazide compound in such a ratio that an amount of hydrazide group is in the range of 0.02 to 3.0 equivalents per one equivalent of carbonyl group in the emulsion particle, and (B) a release assistant; and a method of temporarily protecting a finished coating film of an automobile body, which method comprises coating said coating composition onto a surface of a finished cured coating film coated onto the automobile body.

Abstract: A releasable aqueous coating composition used for temporarily protecting a finished coating film coated on an automobile body. It contains (A) an aqueous acrylic resin obtained by copolymerizing a monomer mixture of a (meth)acrylic ester monomer as an essential component and other polymerizable unsaturated monomer, except for (meth)acrylonitrile, as an optional component, and having a glass transition temperature of 5.degree. to 30.degree. C. and a weight average molecular weight of 20,000 or more, (B) an ultraviolet light absorber, and (C) a water repellent material. A method of temporarily protecting the finished coating film on the automobile body by coating the releasable aqueous coating composition onto a surface of a finished cured coating film coated onto the automobile body.