Abstract: A safety device for a double-circuit type air brake, wherein compressed air is supplied from one compressor to a pair of air reservoirs, through a check valve in each respective route, featured in inserting a safety device in an upstream portion of the double-circuit brake system, i.e., nearer to the compressor than the check valves.

Abstract: A vehicle braking system is provided having alternate, automatically selected actuating fluid circuits, either hydraulic or air circuits, interconnected between a master brake cylinder actuated by a vehicle operator and a brake actuating cylinder that operates the brake shoes at a wheel of the vehicle. A first actuating fluid circuit is normally connected in communicating relationship between the master cylinder and actuating cylinders by fluid-pressure responsive valves. Failure in buildup of fluid pressure in the first circuit when the master cylinder is actuated, such as would be due to a break or leak in the primary actuating fluid line, results in automatic operation of the valves to interconnect a second circuit in bypass relationship to the first circuit. The pressure responsive valves are not operational unless the brake master cylinder is being actuated.

Abstract: A safety hydraulic brake system for automotive vehicles which includes a control cylinder having an inlet connected to a hydraulic pressure source, and first and second outlets connected to brake cylinders at front and rear wheels, respectively. A valve is located at each outlet and normally allows pressurization of the front and rear wheel cylinders upon actuation of the hydraulic pressure source. First and second pistons, each having a by-pass valve, are slidable in the control cylinder. The pistons and by-pass valves are operable, when there is a loss of brake pressure in the lines to one set of brake cylinders, to effect closing of the control cylinder valve to that brake cylinder set. This allows brake pressure to be maintained at the other set of wheel cylinders and the vehicle to be safely braked.

Abstract: An inertial energy storage device is disclosed employing a safety flywheel which is made of flexible material such as a twisted rope ring. The rigidity required for such a device is achieved through centrifugal forces inherent in such a device when it is operating. A small number of the strands of the rope ring have a tensile strength that is lower than the vast majority of the strands of the rope ring whereby should any of these strands fail, they will begin to whiplash allowing such a failure to be detected and braked before a castastrophic failure occurs. This is accomplished by the inclusion of glass tubes located around the periphery of the flywheel. The tubes are in communication with a braking fluid reservoir. The flywheel and glass tubes are enclosed within a vacuum-tight housing. The whiplashing of a broken strand breaks one or more glass tubes. This causes the housing to be flooded with the braking fluid thereby braking the rotation of the flywheel.

Abstract: A fault alarm device for a vehicle dual brake system including front and rear master cylinders, front and rear wheel cylinders and a proportioning valve which functions to develop proportioned rear wheel braking fluid pressure at a reduced rate relative to the rear wheel braking fluid pressure from the rear master cylinder. The fault alarm device comprises a fault alarm circuit for indicating the fault in the dual brake system when energized, and a control valve interposed between the master cylinders and the wheel cylinders and associated with the proportioning valve. The control valve includes a body, a stepped cylinder formed in the body, a stepped piston slidably inserted in the stepped cylinder, and a sleeve slidably interposed between the stepped cylinder and piston. The alarm device further comprises a switch engaged with the stepped piston for energizing the alarm circuit in response to the sliding movement of the stepped piston from its neutral position.

Abstract: A dual circuit brake system has a failure warning section in which the pressures in each of the circuits are sensed by a pair of pistons having a switch actuating shuttle positioned between the pistons by a pair of springs. The ends of the shuttle are telescoped in the pistons for guidance and relative movement. The switch pistons are relatively small with little travel, minimizing displacement loss. The centering springs do not have sufficient load to force the shuttle to the off position once failure in one system has occurred and the pressure in the remaining system has been released. Repair of the failed system allows pressure actuation to move the shuttle back to the deactuated position for automatic reset.

Abstract: An automatic brake mechanism for a milling machine which applies a braking effect upon the machine drive pulley. The automatic brake system includes an actuating device which is responsive to the de-energization of the machine drive motor. The actuating device is effective to forcibly drive a braking element into frictional braking contact with the maching drive pulley whereby preventing the same from continued rotation.

Abstract: A low pressure selector for communicating therethrough fluid from the lower pressure source of a pair of pressure sources includes a housing with input ports for connection to the pressure sources and an output port. A piston member is mounted within a cavity, advantageously formed by walls of the housing, for reciprocating movement therein in response to pressure supplied from the pair of pressure sources to the input ports. Sealing members provided on the piston member cooperatively operate with the walls of the housing cavity and the piston member, to effectuate communication of fluid from the lower pressure source to the output port. The low pressure selector is advantageously employed in a vehicle pneumatic brake system to communicate the fluid from the lower pressure source of first and second sources of supply pressure of the system to a low pressure responsive monitor which warns the operator of the vehicle of a drop in supply pressure from either source below a preset minimum.

Abstract: In a hydraulic brake system of the type having a master cylinder, rear wheel brakes, an actuator disposed between the master cylinder and the rear wheel brakes for controlling the brake pressure increase to be applied to the rear wheel brakes in accordance with the skidding condition of a vehicle wheel, control apparatus for applying a brake pressure increase controlling signal to the actuator, a hydraulic brake booster for operating the master cylinder in accordance with the brake pedal depression, a pressure power source for supplying power pressure to the booster and having the actuating pressure for the hydraulic brake booster utilized as the actuating pressure for the actuator, the improvement comprises the inter-position of a regulating device between the booster and the actuator for increasing the output pressure at the same ratio as the input pressure while the actuating pressure is below a predetermined value and for increasing the output pressure at a smaller ratio than the input pressure when the i

Abstract: A pressure tank connector is described which is formed integral with the cylindrical side wall portion of the tank so that such connector deforms and acts as a safety valve when the fluid pressure within the tank exceeds a predetermined pressure. The deformed connector produces a space between it and an insert member which enables the pressurized liquid or gas within the tank to slowly leak out through such space. In the preferred embodiment, the connector includes a threaded cylindrical connector portion joined by a conical projection portion to the side wall of the tank. The fluid escapes from the tank through a space formed between the threads of such connector and those of an external fitting screwed into such connector.

Abstract: A brake assembly comprises a housing having a piston assembly reciprocally mounted thereon to selectively release the normally "on" brake assembly upon pressurization of an actuating chamber defined therein. The piston assembly comprises an annular piston having an opening formed therethrough to communicate with the actuating chamber. An annular pressure plate is releasably attached to the piston by a plurality of circumferentially disposed bolts. A cover plate is detachably mounted on an outboard side of the piston to normally cover and seal the opening formed therethrough and to further cover at least one of the bolts whereby the cover must be detached from the piston prior to releasing the bolt covered thereby.

Abstract: An accumulator warning system utilizing an electric system with an electric signal and wherein a movable member is disposed in a container having a gas on one side of the member and oil on the other side of the member. The movable member moves toward electric conductors when the gas in the container is depleted, and thus the electric signal is activated.

Abstract: The brake force regulator device is for a dual circuit brake system in which the function of the regulator is suppressed if an uncontrolled brake circuit fails. A locking piston is provided which serves this purpose as well as at the same time to release a differential pressure warning signal should one of the two circuits fail. The advantages achieved with the arrangement disclosed are that only a small amount of pressure fluid is drawn from the intact brake circuit in case of the failure of the other circuit so that the locking piston performs a dual function.

Abstract: An emergency brake system is provided for a vehicle having separate fluid operated front and rear wheel service brakes and a control system with separate front and rear fluid conduits for individually conducting pressurized fluid to effect the application of the service brakes. The emergency brake system includes an emergency brake and a pressure differential detecting device connected to each of the fluid conduits for detecting a difference in the fluid pressures of the conduits. The detecting device is connected through apparatus to the emergency brake to effect the automatic application of the emergency brake when the service brakes are applied and the difference in the pressures of the conduits is beyond a predetermined value.

Abstract: A dual braking system for industrial vehicles of the type in which only two wheels on a common axis are normally braked, and which includes a hydraulic disc brake system in which each wheel has two separate sets of brake cylinders which are connected by separate lines to a common master cylinder. In case of failure of one of the supply lines, a valve interposed between the master cylinder and the brake cylinders closes off the failed line in response to the pressure imbalance caused by the failure. The movable element of the valve is also adapted to close a switch which can be connected in a suitable indicator circuit to warn the vehicle operator that a failure has occurred. According to another aspect of the invention, a floating brake disc is disclosed.

Abstract: A dual hydraulic brake system incorporating a dual master cylinder for separately pressurizing the front and rear brakes of a vehicle. A pressure limiting device is positioned in the brake system for the front wheels which have disc-type brakes. The device prevents the front brakes from being energized until the rear drum-type brakes are functioning and then proportions the pressure applied to the front brakes. Also, an apparatus for providing an indication to the operator of failure of either the front or rear brakes, which apparatus will automatically reset itself upon correction of the failure, is positioned adjacent the pressure limiting device and is responsive to fluid pressure in both systems.

Abstract: A fluid pressure device usable in a vehicle brake system which includes a dual master cylinder inserted into two mutually independent fluid lines which are connected between the front and rear wheel brakes. The device is arranged across the fluid lines between the brake master cylinder and the rear wheel brakes and includes a pair of differential pistons slidably accommodated in a cylinder bore and a balance piston slidable in the bore between the differential pistons, a pair of input fluid chambers being defined between the balance piston and the differential pistons and connected with respective upstream portions of the fluid lines while a pair of output fluid chambers are defined on the outer sides of the differential pistons and connected with the adjacent input fluid chambers through fluid control valves and with respective downstream portions of the fluid lines.

Abstract: A pressure control valve for a braking system having separate pressure circuits comprises a control member movable to control communication between an inlet and an outlet for connection in one of the circuits and spring biased to a valve open position. The control member has an extension which passes sealingly into a space between and sealed from the two circuits and which engages a piston subject to the pressure in the other circuit. The piston is separate from the control member and is operable under the pressure in that other circuit to overcome the spring bias and close the valve by displacing the control member.

Abstract: In a brake system including two independent hydraulic lines extending from a dual type brake master cylinder and connected to the respective rear wheel brakes, a novel pressure control device provided for automatically adjusting the ratio of the front to the rear wheel brake pressure for maximized overall braking efficiency and including failure alarm for warning the driver of any trouble in operation of the device or of any fluid leakage on the hydraulic lines without delay. The device includes a cylinder bore fitted with a pair of annular pistons and a balance piston extending axially therethrough. A pair of sealing rings are mounted on the balance piston at the opposite ends thereof to define each an input and an output hydraulic chamber, respectively connected with the upstream and downstream portions of the associated one of the two hydraulic lines and adapted to be placed in communication with each other with displacement of the balance piston from its neutral position.

Abstract: A motor vehicle hydraulic brake system includes a front brake circuit and a rear brake circuit. The rear brake circuit includes a blend back proportioning valve which controls the pressure in the rear brake circuit. The blend back proportioning valve includes a proportioning piston which cooperates with a valve seat to maintain increases in rear brake pressure proportional to but less than increases in master cylinder pressure between a first predetermined pressure and a second predetermined pressure. A blend back spool moves the valve seat away from the proportioning piston to equalize master cylinder pressure and rear brake pressure when the second predetermined pressure is reached.

Abstract: The invention relates to a tandem master-cylinder for a split braking system of an automotive vehicle. The master-cylinder comprises two pressure chambers, the first one between the control piston and the floating piston and the second or front chamber before the floating piston. The first chamber communicates with a first outlet port which is connected to a second outlet port through a by-pass valve. The by-pass valve is secured to a tappet-rod projecting into the second chamber to be engaged by the floating piston, upon pressure failure in the second chamber and so that the by-pass valve is opened. The first outlet port is adapted to be connected to a set of brake actuators through a braking correcting valve while the second outlet port is adapted to be directly connected to said set of brake actuators.

Abstract: A combination proportioner and a shuttle piston which when moved actuates a brake pressure loss warning switch. A proportioner piston has a spring preload which must be overcome by rear brake supply pressure before the proportioner is actuated. Upon brake release the lips of the switch actuating piston proportioner seal act as a valve to relieve rear brake pressure to the pressure at which the proportioner began to operate. The proportioner is deactivated upon front brake system pressure loss. The proportioner mechanism is so assembled that it can be utilized as an original installation or as a replacement module. In an installation where no proportioning action is required, the shuttle piston and head nut are installed without a proportioning valve. When a proportioning valve is required, a head nut with the proportioning mechanism preassembled therein is installed.