SU1207857A1 - Vehicle braking system - Google Patents

Description

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The invention relates to a transport technique, namely to brake systems of vehicles equipped with pneumatic actuated disc brakes, and may find application in rolling stock of railways and urban electric transport.

The purpose of the invention is to simplify the design with simultaneous reliability.

The drawing shows a schematic diagram of the brake system of the vehicle.

The brake system contains a driver's valve 1, a brake 2 and a feed line 3, as well as a spare tank 4 connected by pipelines, an air distributor 5, a pressure relay 6, a feed tank 7, a brake cylinder 8, as well as a parallel-connected choke 9 and a check valve Yu controlled speed sensor 11, and a pressure reducing valve 12, the inlet of which is connected to the supply tank 7, and the output through parallel connected stop valve 10, controlled by the speed sensor 11, and the throttle 9 with the reserve tank 4. Sensor contacts sk grow 11 vehicle shunted manual switch 13.

The system operates in full service or emergency braking next.

When setting the crank of the driver 1 to the brake position, the air pressure in the brake line 2 decreases, causing braking of the air distributor 5. The air from the reserve tank 4 through the air distributor 5 enters the control cavity 6 of the pressure relay causing air from the supply tank 7 to fill The brake cylinder 8 does not reach the maximum design pressure. Vehicle brakes are activated. In the reserve tank 4, the control cavity of the pressure switch 6 and the brake cylinder 8 are set to almost the same pressure. However, with a decrease in vehicle speed, the friction coefficient of the disc brake friction pair significantly decreases,

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07857. .

as a result, the braking force is reduced and the properties of the friction pair and the clutch coefficient are not fully utilized - the braking distance 5 of the vehicle is increased compared to the calculated one, with the friction coefficient of the friction disc brake pair being calculated.

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Further operation of the system is advisable to consider for different values of speed.

A. When braking at high speed, for example 120 km / h.

Due to the rapid progress of this braking process, the presence of throttles 9, although leading to a flow of some air from the supply tank 7 through the reduction valve 12 to the storage tank 4, nevertheless has practically no effect on the amount of pressure in the brake cylinder 8 in the initial period of braking. However, over time (in the process of reducing the speed to 60 km / h), as a result of air flowing from the supply tank 7 through the pressure reducing valve 12 and the throttle 9 (the shut-off valve 10 is closed) the pressure in the reserve tank 4 increases. As a result of this, pressure rises even in front of the control cavity of pressure switch 6 and, as a result,

35 in the brake cylinder 8. In this case, the pressure limiting the pressure in the brake cylinder 8 is determined by the setting of the pressure relief valve 12. The selection of the diameter of the 40 throttles 9 is determined by the requirement to increase the pressure to the specified limit during the time needed to reduce the vehicle speed from structural speed 120 km / h to a value that allows to realize increased pressure. Under the conditions of the coefficient of adhesion of the wheel to the rail up to 60 km / h. A further braking process occurs at a steady-state maximum pressure in the brake cylinder 8, equal to the setting pressure of the reducing valve 12, which

55 makes it possible to more fully utilize the coefficient of adhesion, the value of which changes during the braking process.

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B. When braking at a low speed, for example 60 km / h or less.

At a driving speed of 60 km / h or less, the speed sensor 11 is applied through the contacts. the control signal to the controlled shut-off valve 10. The shut-off valve 10 opens, however, the brakes are activated to replenish the reserve tank 4 with compressed air from the supply tank 7 does not occur, as well as the pressure to which the reducing valve 12 is adjusted is less than the charging valve pressure. When the driver's crane 1 is placed in the brake position, the brake line 2 is discharged, the air distributor 5 triggers braking, together with the reserve tank 4 with the control cavity of the pressure switch 6. The pressure in the control cavity of the pressure switch 6 increases in the reserve tank 4 - drops . At the time of reducing the pressure in the reserve tank 4 to the setting value of the pressure reducing valve 12, the reserve tank 4 is fed with compressed air from the supply tank 7.

Due to the larger flow area of the check valve 10 compared with the throttle 9, the pressure in the spare tank 4 and the control cavity of the pressure relay 6 increases at a rapid pace, causing the corresponding filling of the brake cylinder 8. The pressure in the brake cylinder 8 reaches the setting value of the pressure reducing valve 12, t. e. maximum value. The properties of the coefficient of adhesion, which vary with the speed of the vehicle, are also more fully utilized.

Editor K. Voloshchuk

Compiled by A. Filippov

Tehred A. Kikemezey Proofreader T. Kolb

Order 151/23 Circulation 648 Subscription

VNII1Sh State Committee of the USSR

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Branch PPP Patent, Uzhgorod, st. Project, 4

207857

B. Braking with an intermediate speed of 120 V 60 km / h.

After actuating the brake and reaching maximum

5, for high speeds of beginning of the braking of pressure in the brake cylinder, due to the choke 9, the pressure in the brake cylinder begins to slow down. When the driving speed is reduced to the value of the setting of the speed sensor 11, the latter delivers a control signal to the shut-off valve 10, the pressure in the brake cylinder at a rapid rate

15 is maxed out, i.e. to the setting pressure of the pressure reducing valve 12, as well as when braking at a speed equal to or less than 60 km / h.

20 If the speed sensor 11 fails, the driver can manually act on the shut-off valve 10 by giving a signal by the switch 13 at the required braking time.

25 For releasing and charging the brake, the crane handle of driver 1 is transferred to the release (train) or charging position and the air from the supply line 3, entering through valve 1

30 into the brake line 2, increases the pressure in it and causes the air distributor 5 to act on tempering and charging. As a result of this pressure switch 6 is triggered on tempering, the release of air from the brake cylinder 8 to the atmosphere - the brake is released. At the same time, filling from the brake line 2 of the reserve tank 4 to charging pressure takes place, after which the handle of the crane 1 of the driver is transferred from the charging to the train position, and the brake is ready for repeated action.

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Claims (1)

VEHICLE BRAKE SYSTEM, comprising a driver’s crane, brake and feed lines, as well as a spare tank, an air distributor, a pressure switch, a supply tank, a brake cylinder, an electrically operated shut-off valve with an inductor mounted parallel to it, controlled by a vehicle speed sensor, and the contacts speed sensors are shunted by a manual switch, characterized in that, in order to simplify the design while increasing reliability, The system is equipped with a pressure reducing valve, the inlet of which is connected to the supply tank, and the output is through a parallel-connected shut-off valve and throttle - with a spare tank, and the pressure setting of the pressure-reducing valve is less than the charging pressure and equal to 9 maximum pressure in the brake cylinder at low braking speeds. S and 1207857 * 1207857