Ferrari

Sound signaling devices for hand brake circuits. Parking brake release alarm. Manual control of electro-pneumatic brake

The proposed device is designed to provide an intermittent sound and light signal to the driver when starting a car with the hand brake on. Its connection diagram is shown using the Moskvich-2140 car as an example, but can be done on other car models.

Handbrake warning light

The driver is notified of a violation of the tightness of the hydraulic system of the wheel brake mechanisms and the activation of the hand brake of the Moskvich-2140 car using one warning lamp installed on the instrument panel. When the handbrake is applied, the lamp lights up with a constant light, which does not always attract the driver’s attention, unlike a flashing one, and often even experienced drivers forget to turn off the handbrake when starting and driving the car. This causes increased wear of the brake linings, additional load on the engine and disruption of the adjustment of the handbrake drive system.
The device, the circuit of which is shown in the figure, consists of a sound generator assembled on transistors VT1, VT2, a multivibrator on transistors VT3, VT4 (relay winding K.1 is connected to the collector circuit VT3); additional switch SB2 and standard elements of electrical equipment - ignition key SA1, hydraulic brake tightness sensor SP, switch SB1 of the handbrake warning lamp and warning lamp HL.
Switch SB2 is installed under the clutch pedal, similar to the brake light switch on the foot brake pedal. When you press the clutch pedal, the contacts of switch SB2 close, and when released, they open.

The device works as follows. When the ignition switch SA1 is turned on, the +12 V supply voltage is supplied to the HL lamp and terminal 5 of the device. By closing the contacts of switch SB1 (handbrake is on), the multivibrator and signal lamp are connected to the negative power bus via the circuit: minus 12 V, closed contacts of switch SB1, terminal 4 of the device, normally closed contacts K1.1, switch SB2 and through diode VD1 to lamp HL . The multivibrator starts working.
Turning on with a frequency of 1...2 Hz, relay K1, with its normally closed contact K1.1, switches the power supply circuit of the lamp, and when the contacts of switch SB2 are closed (the clutch pedal is pressed), it also switches the power supply circuit of the sound generator.
The lamp and generator “produce” an intermittent light and sound signal, respectively. When the contacts of switch SB1 open (the handbrake is off), the lamp and multivibrator are de-energized.
When the SP switch is triggered (the seal of the hydraulic drive is broken), the warning lamp will emit a constant light as usual with this malfunction. The indication of the engaged state of the handbrake when the clutch pedal is pressed will be the same - an intermittent sound signal. This is achieved by separating the circuit of the SP switch and the negative power bus of the device with a counter-connected diode VD1, i.e. minus 12 V can be supplied to the device only through terminal 4 and closing the contacts of the SP switch does not affect the operation of the device.

In table Figure 1 shows the states of the indicators when the driver operates the handbrake (switch SB1) and the clutch pedal (switch SB2) when starting and driving the car with normal and broken hydraulic brake seals.
The device is connected by terminals 1, 2 to the clutch pedal switch SB2, by terminal 3 to the contact of the SP switch freed from the conductor (a) (see Fig. 2). The disconnected conductor(s) of switch SB1 is connected to terminal 4, terminal 5 to the +12 V power bus.

Table 1

	Situation	light indication HL	sound indication HA
1	Power off
	Normal tightness of the hydraulic brake drive
2	Handbrake is on, car is parked
3	Starting and driving the car with the handbrake off
4
5
	Violation of the tightness of the hydraulic brake drive
6	Handbrake is on (off), car is parked
7	Starting and driving a car with the handbrake off
8	Moving the car with the handbrake on
9	Driving a car with the handbrake on
Note: 0 - no indication; X - intermittent indication; + display is constant.

The device uses MP25 transistors with a static current transfer coefficient of 20...35, capacitors - C1, C2 - MBM, SZ - K50-6, MLT resistors, RES-15 relay (passport RS4.591.003.P2), sound emitter capsule DEMSH-1A, switch SB2-microswitch MP-1 with corresponding fastening elements.

Instead of the above, you can use transistors MP26, MP39, MP40 with a current transfer coefficient of at least 20, diodes D7A, D226 and D220, D9Zh, E, relays of any type with an operating current of no more than 30...50 mA and a supply voltage of 12 V.
A correctly assembled and connected device does not require configuration. All its elements are located on a printed circuit board and placed in a metal case.
The installation and relative position of semiconductor elements are not critical. The dimensions depend mainly on the type of relay and sound emitter used.

Long-term operation of the device has shown its reliability, convenience and necessity.

A. KUZEMA, VRL, issue 93

PPZ, automatic “KRM main power supply”, the BKTSU KRO key is set to the “Forward” or “Back” position, the parking brake toggle switch is in the “release” position. When the “release” valve is triggered, all the current passes through the signaling circuit in the control unit:

Resistance, diode, negative wire, which signals the control unit to release the parking brake on the car. When all parking brakes are released, the information on the driver’s monitor about pressing the parking brake disappears both in the information line of the PCU and in the VO.

If the parking brake is not released on at least one of the cars, in the PCB line the information “Art. the brake is pressed" and in the VO mode (carriage equipment), a red rectangle in the line "st. brake" remains.

With the information “Pressed Art. brake" the "Vityaz" system issues the command "Prohibition of movement" to the BUTP.

You can bypass the traffic ban only by switching to control of the train from the KRR. The parking brake position alarm monitors the release of the parking brake, and information about the pressing of the parking brake occurs when the voltage is removed from the “release” valve activation circuit.

Removal of voltage from the “vacation” valve switching circuit will occur when:

Disabled (knocked out) automatic circuit breakers “Main power supply to the control panel”, “Backup power supply to the control panel”;

Malfunctions of the BKTSU (KRO, KRR) keys “Forward” or “Backward”;

Loss of contact or malfunction of the toggle switch “St. brake";

Malfunction of the “released” valve switching circuit.

Therefore, when applying (pressing) the parking brake, it is necessary to check the actual pressing of the parking brakes by the absence of the train rolling away after the pneumatic brakes are released.

ATTENTION! To turn off the parking brake on any car in the event of a malfunction of the BUST (parking brake release valve) or failure to pass the shutdown command, it is necessary to move the handle of the disconnect valve K52 in the parking brake control line from the “Transport” position (the valve handle along the line) to the position “Emergency” (faucet handle perpendicular to the main), i.e. turn the handle 90°. This will lead to the cessation of air supply from N.M. to BUST and air from N.M. will flow through a parallel air duct into the parking cylinder - the brake will be turned off.

Diagram and operation of the safety brake unit (SBB), safety loop

Manual control of electro-pneumatic brake

In normal operation, on model 81-740.1 cars, the air pressure in the TM is 2.7-3.1 atm, the driver’s valve is set to the 6th position, the air distributors are in the brake position. To control the pneumatic brakes of the train, electrical control is used: - automatic and manual.

When switching to KRM, pressure 5 atm. in TM, the pneumatic brakes are controlled by the driver’s crane. The fact that the valve is in the release position is indicated by:

In normal mode, in the upper right corner of the driver’s monitor there are red letters “BTB”;

In VO mode, there is a red square(s) in the “BTB goth” line;

When the KRO or (KRR) is turned off, there are large red letters BTB on the driver’s monitor screen, as well as a lack of pressure in the TC.

When the VR is in the release position and the TE is moved to the “brake” position (disabling the reverse controller), there will be no “emergency brake”. When controlling pneumatic brakes from the KRM, using the electro-pneumatic brake from the KTR button is prohibited.

BTB connection diagram and safety loop operation

The BTB is supplied with a voltage of 75V through the circuit: PPZ, switched on automatic switch “Power supply to the main control unit” or “Power supply to the power supply backup device”, transistor switches BKTSU UT 4 or UT5, open in the position KRO or KRR “Forward” or “Backward”, contacts SD-115 , switched on at a pressure in the TM of more than 2.7 atm. (in the event of a malfunction, they are bypassed by the ABSD toggle switch), normally closed contacts when the RTE toggle switch is off (emergency backup toggle switch), BTB (converter), BARS blocker (turned on in the BARS1 or BARS2 position), BARS keys turned on when the BARS is working, or safety pedal contacts when position of the UOS, neutral wire, the BTB will receive 75V power (Fig. 104).

When 75V power appears on the BTB, the following are supplied with power: contactor K1 and 50V converter. When KI is turned on, it connects transistor switch KL4 to the train wire 524, which is controlled by a microprocessor unit.

On all cars, safety brake valves (SBV) are activated along the following circuit:

50V converter, transistor switch KL4, contacts K1.1, switched-on contacts of the TE toggle switch of the head car, 524 train wire, switched-on contacts of the TE toggle switch of the tail car, contacts K1.1, switched on when K1 of the tail car is turned off, 526 train wire, from wire 526 through VTB in each car for wire 525, 0V voltage converter, BARS blocker, BARS keys when the ARS is on, or PB when the UOS is in position, 0V battery.

The VTB valves turn on and disconnect the air distributors in the BEPP (located in the “brake” position) from the switching valves, and therefore from the taxiway (no air flows into the TC).

The emergency brake is activated when:

Disabling the main or backup reverse controller;

Disabling the machine “Main power supply to the control panel” or “Backup power supply to the control panel”;

Turning on the TE or RTE toggle switches in the head or tail cabins;

Disabling BARS keys;

Disabling PB when operating in UOS mode;

When a train breaks down.

Operation of the TE toggle switch

When the TE toggle switch is turned on in the control cabin or tail cabin, the 50V voltage is removed from the 524 and 526 train wires, the VTB valves lose power, and the emergency brake is activated. The BTB controls the voltage on wires 524;525;526.

When the voltage is removed from the 524 wire, the microprocessor gives a command to turn off the KL4 key, which disconnects the 524 wire from the converter (50V). To turn on the KL4 key, you need to restart the microprocessor, for which you remove and reapply the 75V voltage, which is achieved by switching the KRO (KRR).

Operation of the RTE toggle switch

When turning on the RTE toggle switch:

The contacts of RTE 1 open in the 75V VTB power supply circuit;

The contacts of RTE 2 are closed, connecting train wires 526 and 525 (the potential difference between wires 526 and 525 becomes equal to 0V, VTBs are turned off).

The RTE toggle switch is turned on by the driver in the case when moving the TE toggle switch to the brake position does not result in the emergency brake being activated, which is possible if there is external power on the 526 wire.

The device, the circuit of which is shown in the figure, consists of a sound generator assembled on transistors VT1, VT2, a multivibrator on transistors VT3, VT4 (relay winding K.1 is connected to the collector circuit VT3); additional switch SB2 and standard elements of electrical equipment - ignition key SA1, hydraulic brake tightness sensor SP, switch SB1 of the handbrake warning lamp and warning lamp HL.

Switch SB2 is installed under the clutch pedal, similar to the brake light switch on the foot brake pedal. When you press the clutch pedal, the contacts of switch SB2 close, and when released, they open.

The device works as follows. When the ignition switch SA1 is turned on, the +12 V supply voltage is supplied to the HL lamp and terminal 5 of the device. By closing the contacts of switch SB1 (handbrake is on), the multivibrator and signal lamp are connected to the negative power bus via the circuit: minus 12 V, closed contacts of switch SB1, terminal 4 of the device, normally closed contacts K1.1, switch SB2 and through diode VD1 to lamp HL . The multivibrator starts working.

Turning on with a frequency of 1...2 Hz, relay K1, with its normally closed contact K1.1, switches the power supply circuit of the lamp, and when the contacts of switch SB2 are closed (the clutch pedal is pressed), it also switches the power supply circuit of the sound generator.

The lamp and generator “produce” an intermittent light and sound signal, respectively. When the contacts of switch SB1 open (the handbrake is off), the lamp and multivibrator are de-energized.

When the SP switch is triggered (the seal of the hydraulic drive is broken), the warning lamp will emit a constant light as usual with this malfunction. The indication of the engaged state of the handbrake when the clutch pedal is pressed will be the same - an intermittent sound signal. This is achieved by separating the circuit of the SP switch and the negative power bus of the device with a counter-connected diode VD1, i.e. minus 12 V can be supplied to the device only through terminal 4 and closing the contacts of the SP switch does not affect the operation of the device.

Table 1

	Situation	light indication HL	sound indication HA
1	Power off
	Normal tightness of the hydraulic brake drive
2	Handbrake is on, car is parked
3	Starting and driving the car with the handbrake off
4
5
	Violation of the tightness of the hydraulic brake drive
6	Handbrake is on (off), car is parked
7	Starting and driving a car with the handbrake off
8	Moving the car with the handbrake on
9	Driving a car with the handbrake on

Note: 0 - no indication; X - intermittent indication; + display is constant.

Instead of the above, you can use transistors MP26, MP39, MP40 with a current transfer coefficient of at least 20, diodes D7A, D226 and D220, D9Zh, E, relays of any type with an operating current of no more than 30...50 mA and a supply voltage of 12 V.

A correctly assembled and connected device does not require configuration. All its elements are located on a printed circuit board and placed in a metal case.

The installation and relative position of semiconductor elements are not critical. The dimensions depend mainly on the type of relay and sound emitter used.

Long-term operation of the device has shown its reliability, convenience and necessity.

List of radioelements

Designation	Type	Denomination	Quantity	Note	My notepad
VT1-VT4	Bipolar transistor	MP25A	4	MP26, MP39, MP40	To notepad
VD1	Diode	KD208A	1	D7A, D226	To notepad
VD2	Diode	D223	1	D9Zh, D220	To notepad
C1, C2	Capacitor	0.1 µF	2	MBM	To notepad
C3	Electrolytic capacitor	20 µF 6V	1	K50-6	To notepad
R1, R2	Resistor	18 kOhm	2	0.25 W	To notepad
R3	Resistor	1 kOhm	1	0.25 W	To notepad
R4	Resistor	1.5 kOhm	1	0.25 W

The lamp and generator “produce” an intermittent light and sound signal, respectively. When the contacts of switch SB1 open (the handbrake is off), the lamp and multivibrator are de-energized.

The device is connected by terminals 1, 2 to the clutch pedal switch SB2, by terminal 3 to the contact of the SP switch freed from the conductor (a) (see Fig. 2). The disconnected conductor(s) of switch SB1 is connected to terminal 4, terminal 5 to the +12 V power bus.

Table 1

	Situation	light indication HL	sound indication HA
1	Power off	0	0
	Normal tightness of the hydraulic brake drive
2	Handbrake is on, car is parked	X	0
3	Starting and driving the car with the handbrake off	0	0
4		X	X
5		X	0
	Violation of the tightness of the hydraulic brake drive
6	Handbrake is on (off), car is parked	+	0
7	Starting and driving a car with the handbrake off	+	0
8	Moving the car with the handbrake on	+	X
9	Driving a car with the handbrake on	+	0
Note: 0 – no indication; X – intermittent indication; + display is constant.

The device uses MP25 transistors with a static current transfer coefficient of 20...35, capacitors - C1, C2 - MBM, SZ - K50-6, MLT resistors, RES-15 relay (passport RS4.591.003.P2), sound emitter-capsule DEMS- 1A, switch SB2-microswitch MP-1 with corresponding fastening elements.

A correctly assembled and connected device does not require configuration. All its elements are located on a printed circuit board and placed in a metal case.

The installation and relative position of semiconductor elements are not critical. The dimensions depend mainly on the type of relay and sound emitter used.

Long-term operation of the device has shown its reliability, convenience and necessity.