摘要:
A system for controlling the relative positions of the two pistons in double or opposed piston engines having hydrostatic motion transducers for transmitting the piston energy to a driveshaft. The control is effected by adding fluid to or withdrawing fluid from the transducers. The system includes means for comparing the positions of the two pistons and the angle of rotation of the driveshaft to generate two synchronous error signals, and means for comparing the actual dead points of said two pistons and the predetermined nominal dead points of each piston to generate first and second dead point error signals, and for relating the first dead point error signal to the second dead point error signal. Fluid is added to or withdrawn from the hydrostatic motion transducers in accordance with the synchronous error signals when the engine speed is below a selected engine speed, and in accordance with a dead point error signal when said engine speed exceeds a predetermined speed. In the system, control of both pistons is simultaneously switched from the synchronous error signal to the dead point error signal and vice versa.
摘要:
A turbine bucket includes a bucket airfoil having a tip shroud with leading and trailing edges defining leading and trailing edge profiles substantially in accordance with Cartesian coordinate values of X and Y at points 12-20 and 1-11, respectively, set forth in Table I. The X and Y values are distances in inches which, when respective points 12-20 and 1-11 are connected by smooth, continuing arcs, define the leading and trailing edge tip shroud profiles. An airfoil profile at 95% span is defined by Cartesian coordinate values of X, Y and Z in Table II having the same X, Y origin along the radial Z axis as the origin of Table I. The profiled leading and trailing edges of the tip shroud relative to the airfoil profile afford optimum tip shroud mass distribution which maximizes creep life of the bucket. Stage efficiency is also improved by providing a tip shroud covering the airfoil throat.
摘要:
This invention uses a body force to trap the liquid component of a fluid in local potential minimums in a continuous cavity in an expander. Shaping of the cavity traps the vapor components of the fluid between these "liquid pistons". In the external combustion embodiment, the cavities have a continuously increasing cross section. Therefore, the surface pressure of the fluid generates an unbalanced force on the containing expander. The cavities are shaped such that components of the unbalanced forces combine to generate a torque, which rotates the expanders. In the preferred embodiment, some of this rotational force is fed back by gearing to revolve the expanders around a rotor axis. This revolving generates a centrifugal body force on the fluid in the expander cavities. In the internal combustion embodiment, the expander stages are preceded by decreasing cross section stages which compress the fuel air mixture. The mixture is ignited and expands in the following stages. This expansion allows external work to be done.
摘要:
A fluid actuator for use in a fluid injector assembly including a piston arranged for reciprocation in a chamber, the piston including a connected plunger operating in an injection chamber. A control valve member is actuated to apply fluid to the chamber on opposite sides of the piston to reciprocate the piston and plunger. A fluid throttling arrangement is provided to decelerate the piston towards the ends of its stroke. The fluid actuator may also be associated with an engine valve assembly. A fluid actuated engine piston assembly is also described.
摘要:
The present invention is directed to a free-piston regenerative hydraulic engine including a displacer piston which is driven pneumatically by a high-pressure or low-pressure gas. Actuation of the displacer piston circulates the working fluid through a heater, a regenerator and a cooler. The present invention includes an inertial mass such as a piston or a hydraulic fluid column to effectively store and supply energy during portions of the cycle. Power is transmitted from the working fluid to a hydraulic fluid across a diaphragm or lightweight piston to achieve a hydraulic power output. The displacer piston of the present invention may be driven pneumatically, hydraulically or electromagnetically. In addition, the displacer piston and the inertial mass of the present invention may be positioned on the same side of the diaphragm member or may be separated by the diaphragm member.