IL29816A - Improvements in mastercylinders for oil brakes of motor vehicles - Google Patents

Description

IMPROVEMENTS IN MASTERCYLI DER FOR OIL BRAKES OF MOTOR VEHICLES This invention relates to improvements in cylinders for hydraulic in particular for oil brakes of motor of the kind provided with moving in the longitudinal axis of the mastercylinder for or closing the flow of liquid when pressure is exerted on the brake Most of these cylinders fall to operate when a leakage occur in the liquid conduits leading to the braking There are also known mastercylinders provided safety which are adapted to close the while permitting the other braking system to operate normally and to produce a braking These known mastercylinders are provided with safety valves of rather construction and maintain in the braking eystems continuously a minimum pressure lot they are costly to manufacture and the continuous pressure is dis dvantage in the braking It is the object of the invention to provide for an improved relatively simple which can be relatively cheaply produced having no complicated valves or the like which does not maintain continuous ensuring a braking effect even of a defect in the mastercylinder or of a leaking in one of the liquid conduits to one of the braking According to the invention the mastercylinder comprises two chambers for being adapted to supply liquid for hydraulic pressure each separately to the braking systems of the movable in the longitudinal axis of the first piston in front of the mastercyllnder being adapted to open or to close the liquid supply from one chamber to one of the braking systems and a second piston d the first one for opening or closing the liquid supply to the other braking characterized that chamber connected directly to the liquid conduit for braking the second chamber is connected to the liquid conduit for the other braking system by a bore the wall of the mastercyllnder and a bore in the body of the first each of the pistons being adapted to interrupt the flow of liquid from one of the chambers when a defect occurs the mastercyllnder or a leakage in the conduit to one of the braking systems hile permitting the other braking system to operate The Invention will now be described a non limitative with Reference to the attached drawings which show in t 1 a side view of the mastercyllnder according to the invention in horizontal 2 side view in of a second The mastercyllnder shown 1 consists of an elongated hollow cylindrical portion 1 and of a receptacle for oil positioned normal to portion 1 and being integral Receptacle divided by partition C into two chambers and 1 haB an outlet A leading to the braking system for the rear the front wheels and an open end to be connected to the brake The hollo of cylindrical portion I is divided into spaces G and Chamber D directly with space G by a bore In space G is provided a piston 2 constituted of two a body having a recess rod slidable recess Rod has a piston head and is surrounded by a coil spring Piston head is encased in a housing and between the surface of the bottom of casing and the rear surface of piston head is provided a weak coil spring Chamber E communicates space F by way of a bore provided in the wall of cylindrical portion 1 and a bore in body In space F is provided a piston 3 constituted substantially of the same parts as piston 2 body recess rod 8 surrounded by coll spring 7 having a head 4 encased in a housing 5 biassed by a weak spring Coil springs 7 and abut with their ends remote from the housings and on curved plates and surrounding a projecting part of bodies and of the Body has near its part rubber packings 10 and in recesses near its opposite end part rubber packings Body baa near its projecting part shoulders on which rubber pakings are Rod 8 of piston in the embodiment illustrated shorter than rod of piston his is not rods and S may be of equal The mastercylinder according to the invention works as When pressure is exerted o the brake pedal of the piston 3 moves direction of arrow 3 and closee with its head the bore of Piston thus sealing space F and preventing of liquid into space P from Chamber By continuous pressure on the brake pedal piston 3 is further shifted forwards and pushea piston 2 in direction of bore H and closes bore H with its head thus preventing flow of liquid from chamber D into space The closing of bore creates pressure in the brake system connected to outlet A and the closing of bore H creates pressure in the brake system connected to outlet When the pressure on the brake pedal released springs and 7 return the pistons 2 and 3 into their starting In case a leakage occurs for example in brake system the pressure exerted on the b ake pedal pushes piston 3 against bore and piston 2 which latter closes with its head the bore Thus the pressure in brake system B is maintained while the the brake system A flows but at least brake pressure is exerted on the front wheels and the car can be a leakage occurs in brake system the pressure exerted on the brake pedal pushes 3 against thereby starting to create pressure in system As the leakage occurs brake system there exists no co nte pressure on piston 2 and the latter is pushed in direction bore H by the pressure exerted on piston 3 and closes the outlet 9 of bore In this case the oil ca flow out brake system B but the pressure is maintained in brake system A and therewith on the brake of the rear wheels so that the car can be the The embodiment of the Invention shown in 2 differs from the illustrated in 1 only in that instead of one partitioned receptacle for hydraulic two receptacles and are each coordinated to one of the braking system conduits A and B The eceptacle is communicating directly wit space by bore in the front wall of space while receptacle communicates with space by a bore in the wall of the in the bottom of receptacle and a bore in the body piston bores and MM registering with other during the braking The operation of this embodiment is similar to that described above reference to Receptacles and are Integral with the body of the insufficientOCRQuality

Claims (2)

1. C L A I M S i. A mastercyllnder for hydraulic brakes, in particular for oil brakes of a motor car, comprising two chambers for liquid, being adapted to supply liquid for hydraulic pressure each separatel to the braking systems of the front wheels and the rear wheels of a motor car respectively, and two pistons, positioned one behind the other, movable in the longitudinal asib of the mastercyllnder, a first piston in front of the master-cylinder being adapted to open or qlose the liquid supply from one chamber to one of the braking systems and a second piston behind the first one? for opening or closing the liquid supply to the other braking system, characterized in. that one chamber is connected directly to the liquid conduit for one braking system, while the second chamber is connected to the liquid conduit for the other braking system through a. bore in the wall of the mastercyllnder and a bore in the: body of the first piston, each of the pistons being( adapted to interrupt ' the 'flow of liquid from one of the chambers when a defect occurs in the mastercyllnder or a; leakage in the conduit to one of the braking systems, while permitting the other braking system to operate normally.

2. A mastercyllnder as claimed in claim 1 characterized in that the two chambers are provided in one receptacle Integral with the mastercylinder , the receptacle being divided by a partition. 3· A mastercyllnder as claimed in claim 1 characterized the receptacles being integral with the body of the mastercylinder and presenting the chambers for hydraulic liquid.