A sear mechanism for a firearm includes a trigger element having one or more contact surfaces on which one or more movable or pivotable components of the sear mechanism selectively contacts or slides. In some embodiments, the trigger element is made by producing an intermediate workpiece of the trigger element by a manufacturing process, and electric discharge machining the intermediate workpiece of the trigger element to provide the contact surfaces.

A sear mechanism for a firearm includes a trigger element having one or more contact surfaces on which one or more movable or pivotable components of the sear mechanism selectively contacts or slides. In some embodiments, the trigger element is made by producing an intermediate workpiece of the trigger element by a manufacturing process, and electric discharge machining the intermediate workpiece of the trigger element to provide the contact surfaces.

An electric discharge machine is configured to perform electric discharge machining on a workpiece in a working fluid stored in a work-pan. The electric discharge machine includes: a measurement piping coupled to the work-pan and having an air space inside; a pressure sensor configured to detect a pressure of the air space; and a working fluid supply portion configured to supply the working fluid to the measurement piping.

A rotary-mechanical device, capable of extracting energy from a fluid flow and converting it into rotational motion, may comprise a turbine rotor. This turbine rotor may have an exterior surface extending between two opposing sides. The exterior surface may be formed of a plurality of straight lines, each spanning from a first edge, bordering one of the sides, to a second edge, bordering the opposite side. Each of the straight lines may be disposed in an individual plane running perpendicular to a rotational axis of the turbine rotor, wherein the rotational axis is positioned equidistant between the two sides. A turbine rotor of this type may be formed from a unitary mass by degrading the mass with a wire that may be translated and rotated relative to the mass during degradation.

A piezoelectric actuator that may include a monolithic frame having an integral bias band that provides a resilient restoring force between a first contact surface and a second contact surface of the actuator that may be used to rotate an adjustment shaft. In some cases, a preload mechanism may also be included with the frame. Such piezoelectric actuators may be used for adjustable optical mounting devices such as optical mounting devices.

A method of manufacturing a last chance screen for an aircraft engine includes forming an array of holes through a metal sheet with a wire electrode using electrical discharge machining. The array of holes comprises a plurality of holes. Each hole of the plurality of holes comprises a first end and a second end and is surrounded by a wall section such that the last chance screen is defined by the plurality of holes and the plurality of wall sections. The first and second end of each hole are widened by either applying a flow of an abrasive flow medium to the array of holes in two directions or using a conical sinker electrode on either side of the metal sheet. Shaping the first and second end of each hole results in an airfoil-shaped cross-section of each wall section.

An electrostatic discharge machining fixture includes a fixture body, two or more electrically conductive face contacts seated in the fixture body, and two or more electrically resistive point contacts seated in the fixture body. The electrically conductive face contacts and the electrically resistive point contacts define a 3-2-1 alignment system to locate an additively manufactured article relative to the fixture body during an electrostatic discharge machining operation. Electrostatic discharge machining arrangements and methods of supporting additively manufactured workpieces during electrostatic discharge machining operations are also described.

An electrostatic discharge machining fixture includes a fixture body, two or more electrically conductive face contacts seated in the fixture body, and two or more electrically resistive point contacts seated in the fixture body. The electrically conductive face contacts and the electrically resistive point contacts define a 3-2-1 alignment system to locate an additively manufactured article relative to the fixture body during an electrostatic discharge machining operation. Electrostatic discharge machining arrangements and methods of supporting additively manufactured workpieces during electrostatic discharge machining operations are also described.

An additive manufacturing support device includes reading circuitry that reads shaped article data that is data indicating the three-dimensional shape of a shaped article, first generating circuitry that generates primary data that is data indicating the three-dimensional shape of a primary separated portion provided in a region where a cutting part of a cutting apparatus passes between the plate and the shaped article, and second generating circuitry that generates, based on a machining allowance between the cutting part and an object to be cut in a process in which the cutting part passes between the plate and the shaped article, secondary data for reducing change in the machining allowance.

A wire electrical discharge machine and a wire electrical discharge machining method are provided. The wire electrical discharge machine is equipped with a core position recognizing unit configured to recognize the position of a core which is fixed by a core fixing function, a core removal unit configured to remove the core, which is in the recognized position, from a workpiece on which machining has been performed, and a core removal determining unit configured to determine whether or not the core in the recognized position has actually been removed.