Abstract: A hydraulic machine comprising a rotary toroidal piston chamber with two or more stationary pistons, which are provided to operate in such chamber, and having input and output ports for each piston provides a bidirectional motor or pump operable with high constant torque and high efficiency. Radially movable gates provide closed sections of the piston chamber and open to allow continuous rotation in one direction without reciprocating pistons or cranking mechanism. Rotation of the chamber is achieved by reaction to the force of hydraulic pressure on the pistons. A rotary piston chamber with four stationary pistons, operating as a four piston hydraulic motor simultaneously driving itself as a two piston pump functions as a pressure multiplier providing output pressure higher than the input pressure. Uses include sump pump, pumped energy storage and hydroelectric power generation.

Abstract: A new capacitive tablet has a single layer in which electrodes provide capacitive coupling with a pen to produce signals that correspond to the X and Y dimensions of the position of the pen on the tablet. The electrodes in the single layer are in the form of pairs of complementary shaped, closely adjacent, conductive elements that extend in the Y dimension of the tablet. For sensing the pen position in the Y dimension, an alternating voltage is applied between the two elements of a pair and the pen receives a signal that is a function of the pen position in the Y dimension. The tablet includes a number of such pairs, each having a different X dimension position, and for sensing the pen position in the X dimension, the two electrodes of a pair are given an alternating voltage that differs progressively across the X dimension of the tablet.

Abstract: An improved operation is provided for a graphic tablet of the type in which a pen is capacitively coupled to sets of X dimension wires and Y dimension wires that are digitally activated to produce a pen signal that signifies the position of the pen on the tablet. Compensation is provided for variations in the pen signal that are attributable only to differences in the height of the pen above the tablet as the pen is operated over intervening layers of paper of various thicknesses. The drivers that activate the tablet are controlled to establish a sequence of different activation patterns and a corresponding sequence of analog pen signals. These signals are operated on to produce a pen position address that is substantially compensated for variations in pen height.

Abstract: An improved tablet system is disclosed of the type having an array of X dimension wires and Y dimension wires that are capacitively coupled to a pen that a user holds to the tablet to produce a position signal. The X and Y wires are individually coupled to drivers so that the wires on one side of the pen position can be activated and the wires on the other side can be not activated for a pen position sensing operation. To reduce the number of drivers required for a large tablet, the wires are arranged in groups with an individual driver capacitively coupled to a correspondingly positioned wire in each group. A new packaging arrangement is provided and a new system is provided for addressing the drivers to produce the selected activation pattern.

Abstract: An improved tablet system is disclosed of the type having an array of X and Y dimension wires that are capacitively coupled to a pen that a user holds to the tablet to produce a position signal. Drivers are provided for individual wires to produce a selected activation pattern for the wires. The drivers are operated from a shift register and associated components that are mounted on the tablet and are connected to an associated processor through only a small number of conductors.