Abstract: A pair of electro-acoustic transducers, one functioning as a speaker and the other functioning as a microphone, are operatively coupled to a reference which in turn is in communication with a fluid. A regenerative frequency filtering loop is operatively coupled between the transducers and functions to apply amplified signal to the speaker and produce an acoustic signal which propagates through the medium. The acoustic signal is sensed by the microphone and coupled to the regenerative loop input. For certain frequencies, the spacing between the transducers together with the speed of propagation of sound through the fluid combine with the frequency filtering of the regenerative loop to cause the loop to regenerate at a frequency indicative of the relative speed between the reference and the fluid.

Abstract: A pair of electro-acoustic transducers, one functioning as a speaker and the other functioning as a microphone, are operatively coupled to a reference which in turn is in communication with a fluid. A regenerative frequency filtering loop is operatively coupled between the transducers and functions to apply amplified signal to the speaker and produce an acoustic signal which propagates through the medium. The acoustic signal is sensed by the microphone and coupled to the regenerative loop input. For certain frequencies, the spacing between the transducers together with the speed of propagation of sound through the fluid combine with the frequency filtering of the regenerative loop to cause the loop to regenerate at a frequency indicative of the relative speed between the reference and the fluid.

Abstract: A network processor or other type of processor includes classification circuitry and memory circuitry coupled to the classification circuitry. The memory circuitry is configured to store at least a portion of at least a given one of a number of packets to be processed by the classification circuitry. The classification circuitry implements a non-sequential packet classification process for at least a subset of the packets including the given packet. For example, in an embodiment in which the given packet is generated in accordance with multiple embedded protocols, the non-sequential packet classification process allows the processor to return from a given point within the packet, at which a final one of the protocols is identified, to a beginning of the packet, through the use of a “skip to beginning” instruction. The skip to beginning instruction may be configured to allow the processor to skip back to a particular bit, e.g.

Abstract: A network processor or other type of processor includes classification circuitry and memory circuitry coupled to the classification circuitry. The memory circuitry is configured to store at least a portion of at least a given one of a number of packets to be processed by the classification circuitry. The classification circuitry implements a non-sequential packet classification process for at least a subset of the packets including the given packet. For example, in an embodiment in which the given packet is generated in accordance with multiple embedded protocols, the non-sequential packet classification process allows the processor to return from a given point within the packet, at which a final one of the protocols is identified, to a beginning of the packet, through the use of a “skip to beginning” instruction. The skip to beginning instruction may be configured to allow the processor to skip back to a particular bit, e.g.

Abstract: A variable displacement apparatus includes a pair of axially adjustable housing parts sealingly joined together to form a unitary pumping chamber. A pair of meshing elongated vanes or gears having a plurality of teeth disposed within the chamber in a meshing overlapping relationship for positive displacement pumping purposes. The gears are mounted adjustably within the chamber to move axially therein as the housing parts are adjusted axially relative to one another.

Abstract: The present invention provides a mechanism for initial execution of software code by a processor in a multiprocessor system. In the preferred embodiment, the multiprocessor system has registers implemented at a reset vector location in a processor. The registers are first loaded with a sequence of software code, and then a first instruction loop is implemented with that software code. The processor is then released from a reset state, and the first instruction loop is executed. This first instruction loop is capable of being executed for an indefinite length of time, and it can execute software instructions on a periodic basis. The first instruction loop is then modified into a second instruction loop. The first and second instruction loops have at least one different instruction. The processor within the system of multiple processors is thus initialized.

Abstract: A digital FSK transmitter utilizing a clock feedback signal driving an accumulator to operate a pair of registers having a pair of preset numbers stored therein to selectively add said numbers through a binary adder to the accumulator to output the FSK signal thereby.

Abstract: A digital FSK receiver includes a zero-crossing detector which detects the zero crossings in an FSK signal having at least two signal frequencies. The time interval between zero crossings is then measured with a first interval value corresponding to one of the signal frequencies and a second interval value corresponding to the other signal frequency. An accumulator outputs a digital signal which depends on whether the interval is at the first value or the second value, the digital signal including logical zeros and ones.

Abstract: An improved actuator of the type in which a piston is translatable in a piston housing in response to an expandable working fluid in fluid communication with one end of the piston. An improved sealing assembly prevents leakage of working fluid from the piston housing.

Abstract: An improved electrothermally operated actuator of the type in which a piston is translatable in a piston housing in response to electrical heating of an expandable working fluid in fluid communication with one end of the piston. The working fluid is at least partially disposed in a tube assembly which is connected in an electric circuit which is closed and opened, in response to selected events, to heat or cool the working fluid to effect movement of the piston between retracted and extended terminal positions. An improved sealing assembly prevents leakage of working fluid from the piston housing. The actuator may be connected through a power translating assembly to a rotating element of an operable device translating linear movement of the actuator to rotating movement of the rotating element.

Abstract: A skinning device is provided for assisting in the skinning of squirrels and other small game which comprises a generally U-shaped holder including a front wall and side walls. The front wall includes a single central slot formed in the upper edge thereof, and this slot includes an upper generally V-shaped slot opening, an intermediate, part-circular portion in which the head of the squirrel is received during one step of a skinning operation and an elongate downwardly extending lower portion in which the tail of a squirrel is received during a separate step. A rope or cord connected to the side walls of the holder secures the holder to an upright such as a tree. The side walls include aligned holes through which the cord extends, and these aligned holes are located in the side walls at height relative to the intermediate portion of the slot such that the head of a squirrel being skinned is captured beneath the cord.

Abstract: A ramp assembly provides loading of small off-the-road vehicles onto, and unloading of such vehicles from the bed of a pick-up truck. The assembly includes a flexible support such as a sheet of lightweight chain link, cloth belting or the like which is connected at the upper end to the corner posts of the truck bed or otherwise secured to the truck and which is tensioned at the other end thereof by an elongate support member, connected at one end to the ball hitch on the truck. The connection to the corner posts is made by notched members which extend laterally from both sides of the flexible support to engage the walls of the posts.

Abstract: A relief valve for relieving excessive fluid pressures in a fluid pressure system comprising: a valve body having a cavity therein and an inlet port and an outlet port in fluid communication with the cavity; and a plug assembly carried in the valve body for reciprocal movement between a closed position in which the plug assembly prevents flow of fluids through the inlet port and an open position, in which the plug assembly permits flow of fluids through the inlet port and into the cavity for exit through the outlet port.

Abstract: The present key telephone system comprises cordless telephone stations (FIGS. 6 and 7) which communicate over a line-of-sight transmission end link (276 or 277). The system further comprises a central controller (101) for switching communications between the cordless stations and to the message network. The central controller does not provide any station to transmission channel concentration. Concentration occurs in the bidding by a cordless station for access to a channel provided by the line-of-sight transmission end link. A particular number of transmission channels are provided by the line-of-sight end link which are bid for by any practical number of cordless stations. Subsystem controllers (104) are provided in a large cordless key telephone system. The subsystem controller reformats data for transmission between the central controller (101) and a cordless station.

Abstract: Fluid pressure indicating apparatus which may comprise: a body assembly adapted for connection to a source of fluid pressure; an indicator assembly attached to the body assembly for indicating magnitude of the fluid pressure; a transducer assembly carried by the body assembly for translating pressure applied to one side thereof to linear motion at the opposite side thereof; and an amplification assembly carried by the body assembly between the transducer assembly and the indicator assembly for amplifying the linear motion of the transducer assembly to increased motion at the indicator assembly in predetermined relationship with the pressure magnitude of the source of fluid pressure.

Abstract: Apparatus for treating wastewater includes a settling tank, a sludge digester and a holding tank. Solids from the settling tank are delivered uniformly throughout the seed sludge in the digester and combustible gas is drawn off the top. Sludge from the digester is delivered to the holding tank where further combustible gas evolves and is removed for other uses. The sludge from the holding tank is recycled through the digester or discharged from the system for drying and/or subsequent use.

Abstract: A fast-acting reliable electrically operated normally opened or normally closed valve includes a piston which is spring-biased open and which is actuable by pressurized actuating fluid to drive a plug against a valve seat to terminate working fluid flow. Operating current is passed through stainless steel and copper tubes which are connected in series and contain actuating fluid. The stainless steel tube is heated by the current and vaporizes the actuating fluid-generating pressure which forces the cooler fluid from the copper tube into driving relation with the piston. When current is turned off, the stainless steel tube cools decreasing the vapor pressure. The cooler fluid from the copper tube is forced into the stainless tube by the biasing spring and accelerates condensation in the stainless steel tube to lower the pressure and quickly re-open the valve.