A rate one half random error correcting convolutional coding system capable of correctng two out of any twelve information and parity bits having an encoder comprising a six stage shift register and a modulo 2 adder connected to the shift register for combining the first, fourth, fifth and sixth information bits present in the register to generate parity bits which are subsequently interleaved with the information bits. A decoder employing another six stage shift register generates syndrom bits ...

A case sealer including the usual case sealing devices is automatically adjustable for random size cases. A switching device in the input region of the sealer senses the sizes of the cases entering the sealer, and a brake responsive to the switching device stops any case differing in size from a preceding case. The sealer speeds up in response to the switching device for clearing the sealer of all the cases preceding the different size case, and when the sealer is cleared, an axially movable sha...

A random selector switch having a base, a motor-driven central shaft, two electrical contact arms, diametrically spaced and pivotally mounted on the shaft and of greater length than the distance of their pivot points from the base, and a circular electrical contact, mounted on the base and covering the path the contact arms make with the base when in an at rest condition, the circular contact being divided into at least three electrically isolated contacts, one of block comprises about 180.degre...

A pseudo-random bit generator forms a portion of the pseudo-random code generator, and provides square wave output bits over a defined frequency spectrum on a plurality of parallel output lines. The bits present on a selected number of output lines in sequence define a binary number, which is compared with an accumulated count present in a counter driven by a clock running at a predetermined frequency. A correct comparison resets the counter, shifts the pseudo-random bit generator, and shifts a ...

A strip shingle adapted to be laid on a roof with other identical strip shingles in overlapping superposed courses in a predetermined assembly with adjacent superposed courses offset to simulate the appearance of random width and multiple length wood shingles, said strip shingle having, in its exposed area and its lower edge, slots defining tabs of different widths and lengths with some of the tabs having long and short length portions, the slots in a plurality of the courses being out of vertic...

A random access storage compartment system wherein a plurality of compartments are pivotably attached to a pair of spaced chains supported in a rectangular configuration. The compartments are supported in a level position at all times and any compartment can be selectively moved and halted at an access position.

A self-propelled device adapted to move along the bottom of swimming pools or other water tanks in a random pattern to clean the surface thereof. The cleaner has low-voltage motors for driving, sensing means to sense contact with walls, and electronic logic means to direct the motion of the cleaner according to certain requirements. The cleaner has a suction inlet, a strainer, and is connected by means of a hose to a relatively high-voltage pump above the water level. The logic means provides fo...

Disclosed herein are random graft copolymer compositions comprising base polymers that are amorphous to x-rays at a temperature of 130.degree.C. or below, to which base polymer is randomly grafted, on the average, at least one sidechain of crystallizable homopolymers, of .alpha.-substituted-.beta.-propiolactones and/or copolymers thereof; a process for making said random graft compositions; and use thereof, inter alia, as molded or extruded articles.

A cutter is provided for cutting rope into fibers of varying lengths. A plurality of blades are provided having cutting edges arcuately arranged and facing either inwardly or outwardly. Rope is fed against the cutting edges of the blades, forcing the rope against the cutting edges and through the spaces between them. The planes of the cutting blades diverge from one another, providing an angular blade arrangement such that the spacing between any pair of blades varies along the length of the bla...

A tube expander operable with random length tubing having variable length projection beyond the face of header sheet into which the tube is to be expanded. Rollers in an expander cage are supported on a rotatable mandrel for insertion inward of the tube end. An open ended non-rotatable, tubular thrust collar is adapted to envelop the tube end and is secured about the cage at a predetermined location generally rearward of the rollers. Within the collar and biased toward the open end thereof is a ...