Abstract: A pivotal piston machine or compressor including a disc-like pivotal piston oscillating on a bearing axis, such oscillatory movement being effected by engagement of a roller-type cam follower of a crank arm driven by a crankshaft, with cam surfaces formed on the pivotal piston, and angled member for limiting the oscillating movement at opposite ends of the pivotal stroke of the piston. The angled member serves as a separating wall between two compression chambers and a delivery chamber. A pair of pivotal pistons may be arranged adjacent each other to utilize a common air intake and provide a compound piston machine.

Abstract: A wheel spin control circuit which utilizes conventional anti-skid control apparatus for automotive-type vehicles including an operator's brake valve, brake cylinders, wheel speed sensors, wheel behavior evaluation circuitry and modulator valves to apply braking pressure to a sensed spinning wheel. A solenoid-operated control valve in parallel with the brake valve between the system air reservoir and modulator valves is actuated via a pushbutton switch whenever the operator senses a spinning wheel during acceleration to connect reservoir air to the modulator valves. The modulator valve of the slipping wheel is actuated by control signals emitted by the wheel behavior evaluation circuit to admit the reservoir air to pass to the brake cylinder of the spinning wheel to effect braking thereof. The pressure supply may be continuous or pulsed with or without a pressure-holding cycle.

Abstract: The primary winding of a saturable transformer is coupled to an alternating current source by a series tuned filter network. The transformer secondary winding is coupled to a load network by a second series filter tuned to the source frequency to block harmonics generated by the saturation limiting action of the transformer, which occurs below the normal voltage level of the source and regulates the output voltage supplied to the load within predetermined limits over the source operating voltage range. The first filter is tuned at a predetermined level above the source frequency to cooperate with the equivalent inductance of the unsaturated transformer and output network to hold the secondary output in phase with the input signal at a low levels of the source voltage.

Abstract: The bell clapper arm is mounted on the rotatable armature of a rotary solenoid so as to be moved through an arc, to strike the bell gong with a hammer at its outer end, each time the solenoid is energized. The solenoid energizing circuit includes the contacts of a reed relay switch which are periodically closed by a permanent magnet rotated in close proximity by a motor actuated when a bell warning is desired. The reed relay contacts are closed by the passage of each pole of the magnet and the ringing frequency is adjusted by varying the motor speed.

Abstract: A controllable filter circuit for removing noise from the useful picked up speed sensing signal in an anti-skid vehicular braking system. The controllable filter circuit includes a pickup device, a frequency dependent low-pass filter, a sine-wave to rectangular-wave converter and threshold circuit, a frequency to voltage converter and a switching circuit for actuating the low-pass filter for dampening and blocking troublesome noise signals from the speed signals prior to feeding them to logic, amplifying and output devices.

Abstract: A valve mount for a compressor pressure valve with a valve seat disposed in a bore formed in a cylinder head, wherein the valve mount is provided with a cooling chamber surrounding the external surfaces of a pressure chamber for transferring and dissipating heat from the valve parts including the valve seat.

Abstract: A valve battery device including mounting plates on which valves may be mounted, and of which a preselected number, each having passageways therein, may be assembled in serial relation to form a valve battery of any desired number. Each mounting plate is provided with one hooked projection and one recess for accommodating the hooked projection of an adjacent mounting plate, and all mounting plates are identical in structure and so constructed that they may be turned end-for-end and top-for-bottom so they may universally assemble. Identically structured terminating plates are provided at each end of the valve battery.

Abstract: A disk brake assemblage providing an improved arrangement whereby the brake pads and supports therefore may be changed with a minimum amount of disassembly of the disk brake assemblage. The brake assemblage is provided with an annular cylinder and an annular piston operable therein and comprising a brake cylinder device operably disposed between a pair of backing plates and brake pads which are adapted to frictionally engage respective brake disks or rotors. Both the cylinder and the piston are provided with axially projecting lugs or members normally engaging correspondingly formed recesses on the brake pad backing plates for retaining the brake pads and plates in the operable position. By axially squeezing or displacing the cylinder and piston toward each other, the lugs are displaced out of the recesses to permit the brake pads and backing plates to be removed and replaced.

Abstract: A variable load valve device having a fulcrumed lever, the opposite sides of which are acted upon by respective piston stems of opposing piston assemblies subject to air spring pressure and brake cylinder pressure, respectively. Each piston assembly is independently and axially positionally adjustable relative to the lever to vary the effective differential forces which dictate the level at which brake cylinder pressure is cut off to limit the maximum desired brake cylinder pressure for any given air spring pressure. The desired position adjustments of the piston assemblies are made by adjusting screws engaging the respective piston assemblies which require no changes in spring size or piston dimensions.

Abstract: A brake control system for a railway transit-type train having a control car, on which an electrical brake command is provided, and one or more controlled cars. The electric brake command is converted to a fluid pressure control signal that is connected to a load-adaptive relay valve device on the control car, as well as on each controlled car. Each load-adaptive relay valve is adjusted according to the load condition of a respective car so that the brake pressure of each car is developed consistent with its particular load and in accordance with the brake command in effect. In one embodiment of the invention, the electric brake command is a digital binary code formed by a three-wire control line and converted on the control car to a fluid pressure brake command signal by conventional electro-pneumatic valves and a multi-diaphragm relay valve device.

Abstract: Tire-pressure monitoring apparatus for use with either single or dual tires for signaling deterioration of tire pressure by connecting tire pressure, upon actuation of a valve device by such reduced pressure, to a cylinder device which, in turn, moves a pin member into a space between two adjacent teeth of a rotatable member affixed to the tire, rotatable therewith, and having a plurality of teeth peripherally arranged thereon and alternately interspersed with equal spaces, except one, therebetween. Under normal conditions, the rotating member generates a magnetic field in the proximity of a sensing device which cooperates with the magnetic field for transmitting a series of signals of equal magnitude. If the magnetic field is interrupted by movement of the pin into the spaces, the sensing device transmits either control signals to an anti-skid device or tire-pressure indicating signals to a display panel, depending upon the magnitude of the signals.

Abstract: An overload protection control circuit for marine engines, in which a propeller pitch control signal, as initiated by the operator and transmitted to a servo-positioner for setting the propeller pitch, is modified by a speed control signal, also initiated by the operator, for setting the speed of the ship through a speed governor device, so that the pitch of the propeller is automatically maintained at a degree compatible with the ship speed. According to the invention, an overload limiting valve device is interposed in the protection control circuit and is preset to respond to a critical engine load condition to effect operation of the servo-positioner to a neutral position in which propeller pitch is reduced to a safe degree.

Abstract: A switching circuit for preventing the velocity of the rotating wheels from exceeding the velocity of the moving vehicle in an anti-skid vehicular braking system. The switching circuit includes a first threshold device for generating deceleration and acceleration control signals and a second threshold device for generating positive and negative slip control signals. A logic circuit for evaluating the control signals and controlling the brake pressure and switching devices being activated by a positive slip control signal for blocking the first threshold device from generating the deceleration and acceleration signals and which blocking can be eliminated by the presence of a negative slip control signal.

Abstract: Received periodic pulses of varying amplitude, representing a measured analog signal, are alternately applied to two interpolation channels through gates alternately activated by a flip-flop element responsive to each incoming pulse. Each channel converts the applied pulses into an interpolated value which is summed with that of the other channel to substantially reproduce the original analog signal value. In a first specific arrangement, each pulse is converted, by the integration of the stored pulse amplitude, into a triangular shaped signal having a height equal to the corresponding pulse amplitude and a base equal to twice the pulse spacing. The successive triangular signals from each channel, each overlapping the adjacent pulse signals from the other channel, are summed to produce an interpolated analog output substantially equivalent to the original analog signal.

Abstract: A varistor disc is press-fitted into recesses formed in opposite surfaces of two metal electrodes, its length selected so that a predetermined air gap remains between the electrode surfaces in parallel to the varistor path. The assembly is held by a rivet inserted through the three elements with a spring cup washer under the peened rivet end to absorb dynamic discharge forces. The rivet is insulated by a nylon tube integral with a dust and moisture cover, held at one end by the rivet head and open at its other end for release of gas and particles upon discharge. The varistor dissipates static voltage buildup and low voltage surges. High voltage causes arcing between varistor and electrodes within the air gap, which creates a surge discharge across the air gap between electrodes to dissipate surge energy and protect the varistor element.

Abstract: A ratchet operated chain-type hand brake for railway vehicles characterized by a housing for enclosing the ratchet mechanism and a chain wind-up drum. The ratchet mechanism includes an operating pawl for taking up the chain and a holding pawl for holding the chain take-up, both pawls being in constant engagement with a single ratchet to eliminate lost motion of the operating handle.

Abstract: A varistor element is press-fitted into a recess formed in one surface of a metal electrode and protrudes a preselected distance out from the electrode surface. A second metal electrode is positioned in line with but spaced from the varistor by a TEFLON washer of selected thickness to fix the length of the air gap between the varistor and second electrode. The length of the copositioned air gap between the metal electrodes is similarly fixed by the washer and the protruding portion of the varistor. The assembly is held by a central rivet with a spring cup washer positioned under its peened end to hold elements in contact while absorbing some of the discharge force. The rivet is insulated by a nylon tube integral with an open-end cover for the assembly held at the closed end by the rivet head. When a high voltage surge is applied across the arrester assembly, the varistor-to-metal gap ionizes quickly to initiate discharge.

Abstract: A full disk brake including a pair of disks, brake pads, and a closed external housing. In order to facilitate removal of the housing for changing brake pads, the housing is segmented, such as in the form of a pair of semi-cylindrical segments which are secured to the respective peripheries of oppositely facing disks. The housing segments may be removed independently of the brake actuating mechanism, that is, the wheel cylinder, to permit the pads to be changed. The housing segments may also be mounted such that they may be partially unsecured and then swung out of the way of access to the brake pads.

Abstract: A variable load valve device for modulating brake cylinder pressure on railway freight cars according to the actual vehicle load weight. A load sensing arm detects variations between the sprung and unsprung members of the vehicle to vary the tension of a pair of springs, one of which bias a proportioning valve to a normally closed position and the other of which biases a cut-off valve to a normally open position. The proportioning valve controls fluid pressure communication between the brake cylinder and a volume reservoir, such that when the proportioning valve spring tension is overcome by the brake cylinder pressure, the brake cylinder pressure will be modulated by flowing to the volume reservoir. By reason of the variable spring tension with load, the level of brake pressure at which modulation occurs increases with increased load so that the degree of brake pressure modulation reduces as the load increases.

Abstract: An acceleration servo control system for railroad car retarders in which a computed desired instantaneous deceleration signal and a measured actual deceleration signal are compared and any resulting error signal is fed back through the servo network to adjust retarder braking pressures to achieve and/or hold the desired deceleration rate which will allow the cut of cars to leave the retarder at a selected speed. The desired instantaneous deceleration is computed using an algorithm incorporating actual measured speed, the selected exit speed, the number of axles in the retarder, and the remaining distance-to-go for all axles of the cut over which retarder braking will be effective, and based on the principle of braking each axle-wheel unit throughout the entire retarder length.