Abstract: The system responds to the frequency of pulses from the pulse generator or multivibrator. As the frequency of the pulses increases, they get closer together and the average voltage changes in a somewhat linear fashion. A final integrator amplifier stage is used to find the predetermined maximum current level for different frequency settings. Responsive to this level being exceeded, machining power is interrupted and the EDM operation interrupted.

Abstract: A board played game with the playing board elevated at one end. A pair of score boards are positioned each at a different side of the board with sectors having different numbered indicia in staggered order. The score boards are sized such that their surface is below the upper surface of the board and when the disk rolls over the edge onto each board it will stabilize and take position on one of the marked sectors. Also included on the board is a pair of pegs positioned proximate the lower end by the score boards. The players may be allowed at least three rolls at the bonus pegs which carry a much larger value than the several indicia indicated on the scoreboard.

Abstract: A power supply circuit including a multivibrator and a power output module. Drive signals are provided at low power level and an FET stage is used to provide a high wattage output to operate the power output module. The power output module provides machining power pulses to the gap through a plurality of series resistors so that peak current can be regulated in the module itself.

Abstract: A set of indicator lights, preferably of the light emitting diode type, are used to provide readout from the gap to indicate a gap open circuit condition, a gap normal machining condition, or a gap short circuit condition, respectively. Three lights are preferably contained in a vertical array to give the operator an exact indication of what type of machining is being carried on and hence inform him as to what correction should be made by way of servo feed adjustment, change of machining current, or the like.

Abstract: The servo circuit is operable both in a dual and in a single mode and includes an analog gate for multiple gap inputs. Dual operation is required where more than one gap is involved such as in the situation where multiple electrodes are carried by a common machine tool ram. In the servo operation, the unwanted information over a relatively wide voltage range is eliminated and the more significant voltage excursions around the 30 volt or gap breakdown voltage level are employed. This compensates for the non-linearity that is inherent in the electrical discharge machining gap.

Abstract: A mounting for antennas adapted for use on vehicles having mobile radio communications. The mounting device includes mating male and female members with connection provided by a straight push-in latch including a ball detent latch locked on downward pressure and disengaged by a single pull of a slip ring associated with the female member. The design of the male member allows it to be used as a stud assembly component in a plurality of mobile mounts such as mirrors, racks and the like. The special design modification of the female member further allows it to be used as an assembly component in a plurality of mobile antenna installations.

Abstract: A servo feed control system providing arc sensing for each individual lead in a multiple lead set up. The lowest arc voltage of the several leads in the system determines the feed of the servo system through a hydraulic servo system or the like. Included are a pair of analog switches one of which is actuated responsive to gap polarity so that the system is conditioned to operate with equal facility at either gap polarity.

Abstract: The stand is of a general hemispheric configuration. It is dimensioned with an adapter to handle a broad range of stem sizes and heights of artificial Christmas trees. A principal feature of the stand is the quick mounting and quick release that is made possible by the adapter which is readily expanded or reduced in its diameter when the tree trunk is inserted or removed.

Abstract: A circuit which utilizes a single transistor and a particular resistor combination to form a new slope reversing circuit in which the output voltage is a function of the input voltage with a change of sign for a monotonically varying input voltage. The circuit is valid for a transistor having a high current gain operating in either the active transistor region or the saturated transistor region. The circuit is of particular value when used as a brightness control circuit for a light display used in conjunction with a digital clock for automobile use.

Abstract: A mechanism for substituting a replacement headlight for a burned out or broken one. The mechanism includes a rotating disk and pneumatic actuating mechanism therefor. The actuating mechanism control is operable by the driver from the inside of the vehicle without requiring either stopping the engine or alighting from the vehicle.

Abstract: A photographic exposure unit for making a reproduction of non-dimensional engineering drawings to very close tolerances. The original drawing and the film are driven by a travelling vacuum system through a light exposure unit. In all cases, the exposure is made while the original drawing and film are held in close contact one against the other during their conjoint passage through a flat exposure area.

Abstract: A spiral meat slicer is provided which will form a continuous spiral slice on a piece of meat such as a ham which has a center bone structure which includes a crooked bone of non-uniform diameter.

Abstract: A small model of an aircraft is provided in which the operator is seated in the cockpit. The primary flight controls are selectively operable and actuate six variable speed transformers through the movement of control cables operated by the respective flight controls. The amount of current provided by the transformer outputs is directly proportionate to the degree of control movement. The current is used to activate small, variable speed, reversible electric motors which in turn operate rollers set in pairs and aligned on opposite sides in the three primary planes of rotation of a freely movable sphere contained in the forward aircraft housing. In accordance with the forces imparted to the three different controls, movement is transmitted to the sphere. The sphere itself has included within it a plurality of slide projector units each of which will display or project on a single reflective screen a picture of its own particular portion of the sky or ground.

Abstract: A servo feed system for EDM in which feed of the electrode is controlled responsive to a gap voltage signal with appropriate feedback changes to control servo velocity and upfeed and downfeed gain as the gap voltage level changes. A further feature involves the imposition of a dither circuit between the gap voltage signal amplifier and the servo valve coil in such manner as to continuously apply dither in a manner independent of changes in gap voltage.

Abstract: A current selection and control system for providing uniform steps of machining current magnitude through a plurality of output modules all coupled to a common gap terminal and having individual amplifier stages. The current magnitude output of the modules is weighted in accordance with a binary code so that selection may be made directly through a binary thumbwheel switch and a gating system to enable selected amplifier stages and their associated modules.

Abstract: A fluid drive transmission in which a moving fluid is used to connect the drive and driven members together. The drive and driven members both comprise rollers having longitudinally mounted, spiral shaped vanes extending about their periphery. The rollers are mounted in end to end spaced relationship in a common housing with a greater radial spacing provided between the periphery of the driving member and the housing than between the periphery of the driven member and housing. The system further includes a combined apparatus for supplemental braking which includes a valve connected in a closed hydraulic path between the ends of the housing. The valve is effective to retard the pressurized flow of the fluid upon application of the brakes thus assisting in slowing down the speed of operation of the transmission and retarding the drive output.

Abstract: An engine powered by the internal vaporization of a low boiling point liquid such as Freon which is changed into the gaseous state by a suitable heat source applied to the engine. The engine control system further includes a closed Freon well for condensation of the Freon gas after vaporization in the engine. The vaporization of the Freon within the engine is provided by heat collected by a solar furnace and passed from a oil heat jacket surrounding the engine piston acting as a heat source.

Abstract: A protection circuit which senses and responds to an output transistor failure to provide appropriate power interruption to protect an electrical discharge machining apparatus. The circuit receives an input of either standard or reverse polarity from the gap. This signal is passed through a comparator stage where it is compared with a preset voltage level. Further inputs are provided in accordance with the polarity setting and from the multivibrator in such manner that an appropriate phase relationship is maintained depending on the preset polarity. A control signal is then generated to control a transistor switching device with an interrupt signal thus being furnished to turn-off the power supply. Also included in a different embodiment of the invention is a system whereby, in a multiple gap output module power supply, responsive to failure of an output transistor in any one of the output modules, the entire power supply is cut off.

Abstract: A stand of a generally hemispheric configuration base. A plurality of clamping legs are provided which are arcuately curved and pass through channels formed in the base. The legs will pass through the respective channels into gripping relationship with the tree trunk when it is inserted into a central containing body in the stand. Thus, the weight of the tree itself serves to locate, hold and place into operation the gripping legs of the combination.