Abstract: An ECL bandgap reference voltage generator includes a supply-independent current source (14) to produce an output reference voltage (V.sub.BB) that is independent of variations of supply voltage but yet without consuming additional power dissipation. The supply-independent current source (14) is formed of a pair of transistors (Q907, Q908) and first through third resistors (R903, R904, R908).

Abstract: A cutting device is provided to replace a conventional lawnmower blade which offers improved safety, outstanding grass cutting ability, improved grass bagging suction, and a reduction in the strain on the engine. The device includes an elongated, downwardly curved rigid thermoplastic member having an upstanding airfoil at each distal end. Several elongated flexible tines extend outwardly away and downwardly from the member. The tips of these tines operate to effectively cut the grass while flexing for safety if an object is encountered, such as a rock or toe. The airfoils increase the suction within the mowing cavity to increase the grass bagging efficiency. The downwardly curved configuration presents the tips of the tines for grass cutting while reducing or eliminating the drag of the member on the grass.

Abstract: Method and apparatus suitable for inclusion in an integrated circuit transceiver meeting IEEE 802.3 standards which detects "collisions" so that more than one station will not simultaneously transmit over a network. The method employs a novel three-pole cyclical low-pass filter which attenuates the ac component received over the network to less than 20 mV to allow collision detection within the 900 nanosecond budget allowed by the IEEE standard. A differential operational amplifier receives the signal from the network and a collision reference voltage. The signal generated by the differential amplifier is filtered by the low-pass filter and then coupled to a high-gain comparator which acts as a zero-crossing detector. The comparator generates ECL logic signals representing the occurrence or non-occurrence of a collision. The resulting collision detector operates over a wide range without the need for field "trimming".

Abstract: An operational amplifier suitable for inclusion in an integrated circuit device operating as a transceiver at a coaxial media interface to a network meeting IEEE 802.3 standards. To be included in an integrated circuit package the operational amplifier must have low-power consumption and yet generate up to 80 mA of current onto the network. A design method achieves this goal, producing an operational amplifier having three independently-positioned, isolated, poles. A current generator and level shifter is employed with the operational amplifier which generates a current precisely proportional to a "collision" reference voltage, the current is compensated for changes in temperature and for variations in transistor gain (hFE). A very wide band level shifter matches the current generated to the requirements of the operational amplifier so that 10% to 90% changes in current generated by the op amp can occur in 1/2 to 3/4 of a nanosecond, yet the level shifter does not consume much power.

Abstract: A conveying system is provided, which is particularly designed to convey food over a traffic lane to another traffic lane. The system includes a track extending from inside the restaurant, over the adjoining traffic lane or lanes, to a food-receiving station. A chain-driven trolley is coupled to the track and carries a leveling basket for holding the food or other material being conveyed. In the preferred form, the track includes a high-density, polymer plastic defining two chain-receiving parallel grooves and a third, enlarged, parallel groove. The trolley includes a pair of spaced, track-riders shiftably received in the enlarged groove and coupled to one loop of the chain. Preferably, the trolley includes a basket-locking mechanism and the food-receiving station includes an inclined shoulder. The locking mechanism unlocks before the basket reaches the food-receiving station such that upon reaching the food-receiving station the basket contacts the inclined shoulder, pivoting outwardly towards the customer.

Abstract: A master-slave flip-flop device wherein the master segment employs function and load isolated outputs driven in parallel with cross-coupled latch transistors is described. Signal feed forward may also be provided from a similarly isolated output of the master segment to a device output gate which also receives the otherwise final output of the slave segment. The device is found to exhibit a minimized duration of the undesired metastable state of the master segment and to, thereby, enhance propagation speed in which a stable state is established.

Abstract: The fall-time of an ECL gate is precisely controlled using a fixed capacitor, which is connected between the positive supply voltage and the ECL gate output terminal, and a variable current source connected between ground and the ECL gate output terminal. A time-delay circuit is obtained by controlling the variable current source with an error voltage of a phase-locked loop such that the time-delay precisely tracks the frequency of the reference signal for the phase-locked loop. A signal detector circuit is obtained by combining time-delay circuits. A voltage-controlled oscillator is assembled by connecting 3 ECL gates with controlled fall-times in a ring oscillator configuration. Addition of a non-inverting input to one ECL gate makes the voltage-controlled oscillator interruptible. Combining a voltage-controlled oscillator of the type described with a phase detector fed by a reference signal provides a phase-locked loop with the control voltage thereof providing a frequency-to-voltage conversion function.

Abstract: A carrier rack for bicycles comprises a load-supporting platform composed of a peripheral frame and at least one cross piece that has internal threads at each end. The upper end of each of a pair of struts is clamped between the cross piece and the respective side of the frame by a screw that passes through holes in the side portion and the upper end of the strut and is threaded into the end portion of the cross piece. A rear carrier rack includes a pair of front end connecting bars attached to the platform for adjustment fore and aft. Each connecting bar is a flat metal band, the major portion of which is oriented flatwise to the platform. The front end portion of each connecting bar is twisted approximately 90.degree. so that it lies flatwise to the seat stays. Each connecting bar is connected to a seat stay by an offset ring clamp.

Abstract: A fence is characterized by interchangeably mountable fence sections each having a front and a rear surface, and parallel pairs of vertical and horizontal edges. A mounting member having a mast-receiving opening therein is disposed adjacent each vertical edge of the wall portion of each of the fence sections. Each mounting member has a mating surface thereon disposed in the same plane as the mating surface provided on the other mounting member. When the first mating surface on the wall portion of a first fence section is matingly engaged with a mating surface provided on the other of the mounting members on a next-adjacent fence section, the mast-receiving openings therein are disposed in vertical registration. The fence section, including the wall portions and the mounting members, are integrally fabricated of a plastic material.