Abstract: A control valve lock for a vehicle air brake system is described whereby to secure the parking brakes of the vehicle in an engaged locked position. The lock is securable to the valve actuating rod on the dashboard control valve and is comprised essentially of a block-like base member to which is secured a large actuating knob. A lock cylinder extends through a portion of the knob and the base member and aligns internal locking cavities between the connecting shaft of the knob and the base member whereby the locking dog of the lock cylinder can engage in the cavities to secure the knob in a retracted position whereby to lock the brakes of the vehicle. In order to unlock the brakes, it is necessary to insert a key in the key cylinder to liberate the knob to permit it to be pushed inwardly whereby the dashboard control valve can supply air to the parking brake cylinder to release the brakes.

Abstract: A dismount brake device (1) is tethered by a cable (4) to a snowmobile rider (3). Pulling on the cable (4) displaces a trigger (17) which frees a piston (34). The piston (34) is biased by a main spring (39) to decrease the volume of a chamber (11) containing hydraulic fluid and which is interconnected to the brake line (13). A plunger (36) extends from the head of the piston (34) and seals a port (40) leading to the master cylinder (42). As the volume of the chamber (11) continues to decrease, the pressure in the brake line (13) reaches a value that will activate the brakes and stop rotation of snowmobile track (47). Activation of the brake handle (46) resets the device (1) for further use. An alternate embodiment (48) utilizes a solenoid (50) instead of the tether (4) to physically move a modified trigger (56) when a switch senses that the seat (64) of the snowmobile (2) is unoccupied.

Abstract: The present invention provides for an anti-theft system which is located within a fluid line. This anti-theft system will control the directional flow of the hydraulic fluid in the fluid line. The system of the present invention includes a control panel and a blockage means. The control panel permits for an authorized person to activate or deactivate the anti-theft system. Upon activation or deactivation, a signal is transmitted to a motor via an electrical cable. The motor will activate or deactivate the blocking means.

Abstract: A system for disabling a stolen motor vehicle including a control device and a trigger device. The stolen motor vehicle has a master cylinder housing brake fluid and coupled to brakes by brake lines. The control device controls the flow of brake fluid between the master cylinder and the brakes, initially allowing bidirectional flow of brake fluid. The trigger device triggers the control device to restrict the flow of brake fluid to one direction in response to initiation of the system, tilting of the stolen motor vehicle forward at an angle with respect to ground equal to or greater than a preset angle, and application of the brakes. The trigger device includes a first switch, an operator switch, a motion activated switch, and a brake switch. The first switch is coupled in series between the control device and ground and is initially open. The first switch is operable to activate the control device to restrict the flow of brake fluid to one direction when closed.

Abstract: A parking brake assembly positively engages the drive gear or another component of a wheel drive train and thus cannot slip. Accordingly, the brake assembly can be smaller in size, is less expensive to construct and install, and requires lower release pressures than are required for friction brake assemblies of comparable capacity. When used with industrial vehicles powered via an axle-mounted drive gear, the brake assembly preferably includes a pinion which meshes with the drive gear and a piston on which the pinion is supported. The piston (1) is spring applied towards a first position in which the piston and thus the shaft and the drive gear are mechanically locked from rotation and (2) can be pressure-driven to a second position permitting free rotation of the piston, pinion, and drive gear.

Abstract: In a brake system with an automatic braking mechanism of the present invention, a master cylinder pressure developed by pedaling a brake pedal 1 is supplied to wheel cylinders through first and second brake paths 6,7, first and second center valves 26', 26 and first and second outlets 24', 24 of an automatic broke actuator 8 so that the normal brake is actuated. An electronic control unit (ECU) 40 actuates a thrust generator 38 and thus an automatic braking signal pressure is developed, whereby first and second small-diameter pistons 18', 18 and first and second large-diameter pistons 16', 16 are moved forward to close the first and second center valves 26', 26 to develop pressures which are supplied to the Wheel cylinders, with the result that the automatic brake is actuated.

Abstract: This invention relates to vehicle theft alarm and prevention devices, and in particular discloses a system that operates on the brakes of a vehicles to prevent the unauthorized use of a vehicle. Upon an unauthorized use of the vehicle, the system causes the brakes of the vehicle to remain engaged to the degree to which the user causes them to be engaged by operation of the brake pedal. The harder the brakes are applied, the less mobile the vehicle becomes. The system may be combined with audible delayed alarm signals.

Abstract: Apparatus for indicating the condition of hand brakes on railway cars and for applying and releasing railway car parking or hand brakes automatically in response to predetermined conditions including movement of a train, wayside conditioning apparatus, wayside operating mechanism, a signal controlled by an operator and performance of predetermined railway operating procedures, such as completion of an air brake test procedure. The apparatus may respond to mechanical, electrical and electronic signals and may operate on pneumatic or electric power provided from the service air brake system of a train or from a source of power outside of such air brake system.

Abstract: Disclosed is an air-applied, mechanically-held brake assembly and a vehicle air brake system employing the same. The air brake system typically includes a push-pull or hand-brake valve for park and emergency applications, a treadle valve for service applications, reservoirs of air under pressure, and other valving and plumbing. The brake assembly applies and releases the brake upon the supply and exhaust, respectively, of air from a first pressure chamber. The brake assembly locks and unlocks the brake in an applied position by the exhaust and supply, respectively, of air from a second pressure chamber. The locking mechanism of the brake assembly is designed to compound the force of the fluid pressure in the first pressure chamber with the force of the fluid pressure supplied to the second pressure chamber when unlocking the brake to compensate for back pressure.

Abstract: Apparatus for indicating the condition of hand brakes on railway cars and for applying and releasing railway car parking or hand brakes automatically in response to predetermined conditions including movement of a train, wayside conditioning apparatus, wayside operating mechanism, a signal controlled by an operator and performance of predetermined railway operating procedures, such as completion of an air brake test procedure. The apparatus may respond to mechanical, electrical and electronic signals and may operate on pneumatic or electric power provided from the service air brake system of a train or from a source of power outside of such air brake system.

Abstract: An automatic vehicle brake locking system, including an actuator (16) which segregates an auxiliary hydraulic fluid pump (42) from the normally used vehicle master cylinder (2). The actuator (16) is formed as a cylinder including a piston (36) which is biased to permit passage of hydraulic fluid which is pressurized by the vehicle master cylinder (2) through the actuator (16).

Abstract: A vehicle anti-theft system includes components for engaging the brakes of the vehicle through the vehicle's hydraulic brake lines. In its preferred embodiment the system includes an auxiliary vacuum booster, an air plunger and cylinder assembly, a compressor for producing compressed air for moving the plunger, an arm connecting the plunger with the vacuum booster, an auxiliary brake master cylinder, and hydraulic fluid lines between the auxiliary brake master cylinder and the conventional fluid lines of the vehicle. Once parked, the compressor automatically engages and pressurizes the plunger and cylinder. The plunger presses against the vacuum booster utilizing the remaining vacuum available from the existing system. The vacuum booster acts against the auxiliary master cylinder to apply pressure on the fluid lines between the auxiliary master cylinder and the vehicle's existing hydraulic lines, thereby locking the vehicle brakes.

Abstract: An anti-theft device for a motor vehicle equipped with hydraulic brakes. A key switch is electrically connected to the vehicle's battery and to a small motor. When the key switch is turned, power from the battery causes the motor to reciprocate a piston which is connected to a valve. The positiion of the piston either blocks or unblocks the flow of hydraulic fluid between the brakes and the hydraulic fluid reservoir while one-way flow is allowed between master reservoir and brakes whether the device is armed or unarmed. The key switch and connecting wiring are isolated from the ignition system, preferably passing through the structural frame of the vehicle.

Abstract: The invention is directed to an automatic standstill brake for motor vehicles equipped with an automatic transmission wherein a braking pressure is generated at the wheel-brake cylinders via devices operating on the brake circuit of the motor vehicle. The automatic standstill brake prevents a rolling of the motor vehicle when at standstill. The standstill brake operates when the motor vehicle has come to standstill and the driver has released the brake pedal so that it goes into its rest position. The standstill brake includes a computer which provides an output for a signal transmitter which supplies an actuating signal which, in turn, is applied to the devices operating on the brake circuit thereby causing the standstill brake to become engaged or disengaged.

Abstract: Disclosed is an air-applied, mechanically-held brake assembly and a vehicle air brake system employing the same. The brake assembly applies and releases the brake upon the supply and exhaust, respectively, of air from a first pressure chamber. The brake assembly locks and unlocks the brake in an applied position by the exhaust and supply, respectively, of air from a second pressure chamber. The locking mechanism of the brake assembly is designed to compound the force of the fluid pressure in the first pressure chamber with the force of the fluid pressure supplied to the second pressure chamber when unlocking the brake to compensate for back pressure.

Abstract: A security brake system comprising a plurality of braking modules, each module coupled between a brake master cylinder and a set of wheel cylinders of a vehicle, each module further comprising a body having a first, second, third ports, and a plurality of channels disposed therein between the ports, the first port allowing the transfer of braking pressure to the body from the brake master cylinder, the second port allowing the transfer of braking pressure from the body to a set of wheel cylinders, the channels transferring brake pressure therethrough between the ports; a valve mechanism coupled to the third port of the body and extended within a channel between the first and second ports for controlling brake pressure between the first and second ports, whereby allowing the brakes of the vehicle to be locked or unlocked; and an activation mechanism for activating the valve mechanism in one orientation, whereby unlocking the brakes of the vehicle, and deactivating the valve mechanism in another orientation, th

Abstract: An anti-theft device is coupled in series with a supply line and a service line of a trailer. When activated, the anti-theft device prevents theft of the trailer by decoupling the supply and service lines of the trailer from the reservoir and brake cylinders of the trailer, and by coupling the supply and service lines to the atmosphere, thereby preventing a prospective thief from releasing the trailer's brakes by restoring air to the supply and service lines. When the anti-theft device is deactivated, the supply and service lines are re-coupled to the reservoir and brake cylinders to allow the driver to release the trailer brakes.

Abstract: A brake release lock interposable between the master cylinder of a hydraulic vehicle braking system and the wheel cylinders, including a first connecting element for connection to the master cylinder, a second connecting element for connection to the wheel cylinders, a first passageway connecting the first and second member, having a valve seat and bore for a check valve spring-biased against the seat and configured in such a way as to permit fluid to flow from the master cylinder to the wheel cylinders, but to prevent fluid from returning from the wheel cylinders to the master cylinder, a second passageway connecting the first and second connecting elements, bypassing the first passageway, and a solenoid valve responsive to signals producible by an authorized user of the vehicle, for cutting off the second passageway after the vehicle has been parked, and for re-establishing the second passageway prior to driving off the vehicle.

Abstract: An anti-theft device for protecting air brake control valves from being manipulated is disclosed. A clamp assembly locks on to the valve knobs employed to release the air brakes in a vehicle. A pair of blocks incorporate a key lock assembly and posts to enable portable use of the device. This device is readily adaptable to lock more than one type of several standard brake valve knob sizes by utilizing removable inserts. Impact-resistant plastic or metallic compositions may form the bodies.

Abstract: The present invention relates to a vehicle anti-theft system which, when activated, will block the vehicle's hydraulic brakes into the locked position preventing the vehicle from being driven or towed. Once activated, the system is immune to power failure. The system can use one of several control means to activate the system including keypad, scanners, key system, or wireless remote.

Abstract: An anti-theft device is installed in a vehicle brake line which carries braking fluid. The device defines a valve seat and a valve body adapted to close against said valve seat, the valve body having a passageway therethrough and being rotatable against said seat about an axis substantially perpendicular to the passageway, between a first position in which it permits fluid flow in one direction and inhibits fluid flow in the opposite direction, and a second position in which it permits fluid flow in both directions. The valve can easily be switched between the first and second positions, and can be locked in the first position. By allowing braking fluid to flow only toward the wheels, it will be evident that the wheel brakes, once applied, cannot, be released.

Abstract: The invention relates to a master cylinder comprising a body (12) comprising a bore (14) in which slides, in leaktight manner, at least one piston (16, 18) movable between a rest position and at least one working position and defining at least one pressure chamber (20, 22) connected to an application fluid system, the piston (18) having a peripheral groove (44). According to the invention, a finger (42) actuated by an external mechanism (46) is capable of entering the groove (44) so as to lock the piston in one of its positions.

Abstract: A braking device for small recreational vehicles, such as roller skates or skateboards, having brake pads positioned in close proximity to the wheels of the recreational vehicle. The brake shoes are brought into operative contact with the wheels to effect braking under the action of a hand squeezable bulb. The braking assembly transmits the pressure created from squeezing a bulb through a conduit to a pressure activated member, such as an inflatable bladder, to displace the brake shoes to their braking position. Braking pressure may be maintained through the use of a valve. The braking conduit may be easily disengaged from the pressure activated member so that the recreational vehicle may alternatively be used in a conventional fashion having no braking capability.

Abstract: A railway brake actuator which provides both service and parking braking comprises a cylinder having an operating cavity. A piston assembly in the operating cavity has a stepped bore forming second and third cavities and is extended by hydraulic pressure and retracted by a spring to apply and release the service brake. Hydraulic pressure extends a hollow parking brake piston from the second cavity to extend the piston assembly and apply the parking brake. A one-way clutch comprising ramps and rollers locks the piston in parking brake applied position. Hydraulic pressure disables the clutch to enable spring retraction of the parking brake piston and the piston assembly to release the parking brake. A gripper ring on the piston assembly operates between cylinder abutments to limit piston assembly retraction to provide slack, and enables slippage on the piston assembly on extension to adjust for brake wear.

Abstract: An apparatus for actuating a hydraulic brake has a housing with a cavity communicating with an input and an output for hydraulic fluid. The housing is adapted to be positioned between a master cylinder and a wheel cylinder in a vehicle hydraulic brake system. The cavity receives a valve apparatus in the form of a sleeve and a piston for opening and closing to control a flow of hydraulic fluid. The cavity also receives a seat, and the seat movably receives a transmission assembly that communicates with the valve apparatus. A driving system drives the transmission assembly to actuate the valve apparatus. A control circuit receives a code from a user to activate the driving system. A measuring device determines a duration of activation of the driving system. The valve is open during normal operation of the vehicle. To lock the brakes for security, the code is entered and if correct, the valve closes, thereby acting as a check valve. Hydraulic medium is forced through the valve to the wheel cylinders.

Abstract: An anti-theft system for vehicles pressurizes and locks the hydraulic brakes whenever voltage is removed from a special master brake cylinder. The master brake cylinder has all the conventional parts, but the central rod which carries the hydraulic pistons extends past the usual point and attaches to a permanent magnet at the end of the rod. A coil spring forces the rod in the direction of rod movement needed for brake activation, toward a solenoid. The solenoid is powered by the vehicle battery. The spring is prevented from continuously engaging the brakes by the magnetic repulsion of the permanent magnet by the solenoid. The magnetic force acts to disengage the brakes. When the current is cut off, so is the magnetic repulsion, and the unbalanced force of the spring pushes the rod to engage the brakes. The solenoid current can be switched on or off by a remote switch. The switch may be closed and opened remotely through a radio link.

Abstract: An assembly is provided for use with a trailer including a plurality of wheels, normally engaged air brakes coupled to the wheels, and an air supply line coupled to the air brakes for supplying air to release the air brakes. The assembly includes a valve for selectively venting the air supply line to the atmosphere to prevent the release of the air brakes from their normally engaged position. The valve is coupled to the air supply line and is adjustable between a first position and a second position. In the first position, the valve seals the air supply line to permit the air brakes to be released when air is supplied to the air supply line. In the second position, the valve vents the air supply line to the atmosphere. When the valve is in its second position and air is supplied to the air supply line, the air is vented to the atmosphere. Therefore, in the second position, the valve means prevents the air brakes from being released when air is being supplied to the air supply line.

Abstract: Disclosed is a brake locking mechanism of the anti-theft type for use with a vehicular brake system having a brake actuating push rod reciprocable by a driver operated lever into the brake applying position. The brake lock comprises a locking mechanism attached to the brake pedal by an elongated linking member and a remote switch for engaging and disengaging the lock. The locking mechanism preferably comprises a pawl and ratchet assembly or a piston and fluid operated cylinder. The lock may be either manually activated by pressing on the brake pedal or automatically activated by positioning a three-way valve and engaging a pump.

Abstract: A parking brake having an output lever connected at a first pivot point to a brake rod, at a second pivot point to a automatic fluid responsive actuator and at a third point to one end of a chain of a standard manual releaseable parking brake unit. The other end of the chain is connected to a reset lever which is activated by the automatic actuator to reset the manual parking brake unit after manual release and during automatic release. The automatic actuator includes an air bellows to drive a piston, and a simple interlock valve connecting the air spring to a brake line.

Abstract: Three stacked components are bolted together. The uppermost component supports a key-controlled actuator which vertically shifts three rods. One of the rods operates a switch. Each of the other two rods controls the flow of fluid in a brake line. Each brake line includes parallel passages in the intermediate and lower body components. The parallel passages are interconnectd by a bypass passage of smaller diameter than the parallel passages. The parallel passages are further interconnected by a one-way valve passage downstream of the bypass passage. Each one-way valve passage includes a spring biased ball which permits fluid flow to a brake cylinder but prevents reverse flow. Each of the other two rods is slidable into anti-theft position to block fluid flow through the associated bypass passage, but permitting fluid flow through the associated one-way valve to a brake cylinder.

Abstract: A vehicle anti-theft system is activated by a magnetically coded card and associated card reader to activate a normally closed solenoid valve which is connected in the brake line to permit normal operation of the vehicle, the valve being closed when unoperated, preventing brake fluid to return to the master cylinder, whereby the brakes of the vehicle are locked, preventing operation of the vehicle. The valve has its fluid inlet connected to the brake line and its fluid outlet connected to the outlet of the master brake cylinder.

Abstract: A flow control device for use in a fluid or gas line is disclosed. In one example, the device controls the flow of air to the brakes of a large vehicle such as a semi-trailer truck. The device includes a housing having an inlet port and an outlet port both of which communicate with the interior of the housing and a moveable valve assembly which selectively can close or open the ports with respect to one another. The valve assembly includes means for axially moving the assembly and locking it in open and closed positions. Means are provided for biasing the valve assembly to an open position to prevent accidental closing of the valve which possibly could result in the application of brakes of the vehicle.

Abstract: An automatic brake locking system, for locking the brakes of a vehicle having a hydraulic brake system, is operated every time the ignition switch is turned off to apply pressure through an auxiliary brake actuating device to lock the brakes and hold them locked until the auxiliary brake actuating device is released. A safety switch is provided to operate in conjunction with the ignition switch; so that the safety switch and the ignition switch both must be operated to an "on" position to release the auxiliary brake actuating device to allow normal operation of the vehicle. Turning on the ignition switch without operation of the safety switch does not permit movement of the vehicle since the auxiliary brake actuating device continues to be operated. The system is a passive system, which it does not require any separate actions on the part of the vehicle operator to cause the auxiliary brake actuating device to be operated when the vehicle ignition switch is turned off.

Abstract: An automobile brake system includes a master cylinder, a wheel cylinder and a solenoid actuated valve between the master cylinder and the wheel cylinder. The solenoid actuated valve is actuatable for maintaining high fluid pressure in the wheel cylinder after a brake pedal associated with the master cylinder has been released in order to prevent unwanted rearward rolling movement of a vehicle once it has stopped.

Abstract: An air brake system with a multifunction control valve; a multifunction control valve for an air brake system; various sub-valves within the multifunction control valve--including a pressure protection valve, a pressure reducing valve, an emergency control valve, and a syncro valve. In one embodiment all four types of sub-valves are within a single unitary housing of the multifunction valve.

Abstract: A parking maintaining apparatus includes a solenoid-operated open/close valve which opens or closes a constant pressure passage providing a communication between a valve mechanism and a constant pressure chamber of a brake booster. A relief valve is provided which relieves a pressure within the constant pressure passage into the constant pressure chamber when such pressure exceeds a given value. The provision of the relief valve allows the pressure within a variable pressure chamber to be maintained at or below the given value through the valve mechanism under a parking maintaining condition, whereby the pressure within the variable pressure chamber can be rapidly displaced as the parking maintaining condition is to be terminated, thus eliminating a partly braked condition.

Abstract: A magnetic valve with a connection device is proposed, in which the housing is rotatable relative to the connection device, which encompasses a connector stub formed onto the housing. Embodying the connection device as a male fitting enables the alignment of the housing and the cable plug located on it, which is especially useful when the magnetic valve is installed in a wheel connection of a master brake cylinder. In another version, in which the connector stub is connected to the connection device positively with a snap-in ring, the magnetic valve can be inserted even at inaccessible locations. If the connection device is embodied as part of a brake cylinder, then the magnetic valve can be inserted directly, and the result is a connection that is secure against manipulation.

Abstract: In a vehicle such as a tractor or a trailer having fluid-operated spring brakes to which fluid is supplied under pressure for releasing the brakes from a locked condition, security means are provided to prevent unauthorized release of the brakes. The security means comprises a bistable solenoid valve for controlling the supply of fluid to the brakes, energizing circuit means for operating the valve, and limited access switching means operable to set the solenoid valve selectively in an open or a closed condition.

Abstract: A vehicle anti-theft system which is activated by a key switch or by a magnetically coded card and associated car reader to activate a latching solenoid valve to one state for disabling functions of the vehicle, preventing operation of the vehicle, or to the opposite state for enabling operation of the vehicle. The system requires a specified voltage at a level higher than the voltage of the vehicle battery to prevent compromising of the system as by the use of jumper cables or the like.

Abstract: A fluid brake system has a brake pipe, a control valve device, a brake cylinder and a brake rigging, and in addition, a handbrake pipe, a protective device, a fluid pressure releasable spring handbrake cylinder, and a manually operable handbrake device for selectively governing brakes of the brake rigging under varying conditions, as when air supply is disconnected from a train. A moveable fulcrum in the manual handbrake device permits manual release of spring applied handbrakes in combination with a resetable toggle locking connection to a handbrake rod.

Abstract: In a hydraulic brake system for a vehicle of the kind comprising a fluid pressure source having a reservoir and a hydraulic booster having a power piston arranged to receive the pressure fluid of a control fluid chamber which is proportional to a stepping down force on a brake pedal, a normally open type valve is disposed in a fluid passage provided for returning the pressure fluid of the control fluid chamber to the reservoir and is arranged to close in response to a braking pressure retaining signal produced when the vehicle is stopped by brake application.

Abstract: An anti-theft hydraulic brake device is provided and consists of a valve placed in hydraulic fluid conduit going from a master cylinder to wheel brake cylinders that will keep the brakes locked when the valve is activated from the dashboard after the brake pedal is released. In a modification the valve can be selectively operated from the key operated ignition switch as an additional safety factor.

Abstract: A booster unit for moving a vehicle on a slope and having a booster and a master cylinder coupled to the booster, comprising a brake fluid pressure holding valve having an actuator and provided at a brake fluid pressure piping system for either maintaining or releasing the brake fluid pressure in accordance with the conditions of the vehicle on a slope, a plurality of sensors for detecting the vehicle conditions and a control unit including a microprocessor having a CPU, a RAM, and a ROM so as to receive detected signals from the sensors and to calculate and produce control signals to the actuator of the brake fluid pressure holding valve in accordance with the conditions of the vehicle on a slope, and a method of controlling the booster unit. With this construction, a smooth moving of the vehicle can be realized on a slope.

Abstract: A two-way check valve is utilized with each brake assembly to apply pressure against a single actuating diaphragm. One inlet port is connected to the service air supply and one inlet port is connected to the emergency air supply. Satisfactory pressure of either supply operates the brake connected to the brake assembly in a service manner, the loss of air pressure in either supply causing that supply to be closed by the check valve. Emergency air venting from a spring-biased piston with a pawl end causes the pawl to engage a rack surface of the brake actuator rod. Hence, no spring is used to power the brake actuator rod and brake connected thereto closed when there is a loss service air pressure.

Abstract: A brake control apparatus for a vehicle includes brake apparatus for the respective wheels which are operated by pressurized fluid from a master cylinder; an electro-magnetic valve arranged in a conduit connecting the master cylinder with at least one of the brake apparatus, the electro-magnetic valve being normally in the communicating state and being changed over into the intercepting state by an external instruction; at least one of the brake apparatus being of the disc brake type, the one comprising; (a) a disc rotor; (b) first and second friction pad assemblies for engagement with opposite sides of the disc rotor, the assemblies being guided for movement towards the disc rotor; (c) a caliper body straddling the peripheral edge of the disc rotor and the first and second friction assemblies; (d) an actuating member arranged in the caliper body for urging the first and second friction pad assemblies into engagement with the disc rotor, and (e) elastically deformable retainers for supporting the first and se

Abstract: Automobile theft is running rampant throughout the country, and many automobile stealing organizations are well organized, and have the necessary techniques to enable them to select and steal virtually any automobile. In a matter of a few hours they can change numbers, and other identifying data and give the automobile a new identity and appearance so that the automobile can be quickly sold at somewhat reduced prices. The overall profits are indeed very substantial. We have devised a theft proof locking system, including a key operated unit, which can be positioned at any desired location in the vehicle, and is operable to fully apply the brakes to all four wheels of the vehicle. This renders the vehicle immobile, even though the engine can be started and run. The only way that this locking system can be rendered inoperable is by the act of unlocking it with the key. It is therefore impossible to move the vehicle without lifting it bodily to load it onto a trailer or transport.

Abstract: A parking brake valve cooperates with a spring loaded cylinder which releases a parking brake when pressurized. The valve includes a shaft with an eccentric section, and this shaft may be turned by an actuating lever from a position in which the brake is engaged to a released position. In the released position, the eccentric section of the shaft causes the movement of a control piston, permitting the spring loaded cylinder to be pressurized, releasing the brake. The pressure applied to the spring loaded cylinder is also provided to a radial surface on the shaft, causing the shaft to be friction locked in the released position, despite a spring force applied by a control spring tending to return it to the braking position. If a breakdown occurs in the parking brake system, however, the pressure to the spring loaded cylinder will drop, releasing the friction lock.

Abstract: Devices for preventing the theft of vehicles and trailers are known, of which vehicles and trailers the decelerating brakes and parking brake consist of brakes operated with compressed air. The device comprises a valve controlled by a code lock. In order to double the safety against manipulation of the locking device, the valve consists of a three-way valve (14) with one inlet port and two outlet ports (16,17), which valve (14) is inserted in the feed line (11) between a pressure medium source (4) for actuating the parking brake and the control valve (12) for the parking brake, with the inlet port connected to the pressure medium source (4). One outlet port (16) is connected to the control valve (12), and the second outlet port (17) is connected to the decelerating brake circuit for either wheel pair (1) via a first check valve (19).

Abstract: A vehicle brake control system for the wheels (122) of a vehicle wherein each wheel (122) includes a brake assembly (110) is provided. The control system includes tanks (14, 16) containing pressurized fluid. Brake actuators (21, 22, 23, 24) are interconnected to the wheels (122) of the vehicle for controlling a mechanical lock (162) for the brake assembly (110) associated with each wheel (122). A control unit (40) is interconnected to the tanks (14, 16) and the actuators (21, 22, 23, 24) for supplying fluid from a tank (14, 16) to the actuators (21, 22, 23, 24) to control the engagement and disengagement of the brake lock (162) in the event of loss of pressure in either of the tanks (14, 16).

Abstract: An air brake includes a service brake chamber which actuates a push rod. A collet brake chamber is partially defined by a collet brake diaphragm. A locking collet is mounted to the collet brake diaphragm and includes a bore through which the push rod passes. A collet brake spring biasas the collet into a tapered collet hole to clamp the collet onto the push rod to prevent the movement of the push rod toward the brake off position. Application of pressure to the collet brake chamber overcomes the force of the collet brake spring and moves the collet away from the tapered collet hole to allow the push rod to move freely. The collet can be moved towards and locked against the collet brake spring to prevent the collet from engaging the push rod. This allows the user to effectively deactuate the collet brake feature when desired, such as to mechanically release the push rod from the collet when the vehicle is stationary.