CN107588904A - A kind of bus brake system system air tightness detection system and its detection method - Google Patents

Abstract

The invention discloses a passenger car braking system air tightness detection system and a detection method thereof, comprising an air pump, a condenser, a dryer, an air pressure sensor, a first electromagnetic valve, a second electromagnetic valve, a four-circuit protection valve and an air storage tank , one end of the condenser is connected with the air pump, the other end is connected with the drier, one end of the air pressure sensor is connected with the drier, and the other end is connected with the air inlet of the first electromagnetic valve, and the air outlet of the first electromagnetic valve leads to A four-circuit protection valve, the four-circuit protection valve leads to four air storage tanks, and a second electromagnetic valve is arranged between the four-circuit protection valve and the air storage tanks. The invention can sense the air pressure change of each circuit in the brake pipeline in a short time, and determine whether the vehicle can pass the airtightness test of the whole vehicle according to the reference value of the air pressure drop.

Description

A passenger car brake system air tightness detection system and detection method thereof

Technical field:

The invention relates to a passenger car brake system air tightness detection system and a detection method thereof.

Background technique:

At present, the braking system of passenger cars generally adopts a double-circuit air braking system. The air tightness of the brake pipeline directly affects the performance and energy consumption of the bus. Especially for pure electric buses, poor air tightness will As a result, the air pump works for a long time, the dryer fails, and the valves are damaged. Generally speaking, the air tightness detection method of the bus factory is relatively rough, and most of the bus factories are still at the stage of spraying each air pipe with soapy water, and detecting whether there is air leakage by observing the change of the foam, this method is inefficient , Time-consuming and labor-intensive, and the inability to accurately observe small air leaks and other defects.

Invention content:

The present invention provides a passenger car brake system air tightness detection system and a detection method thereof in order to solve the above-mentioned problems in the prior art.

The technical solutions adopted in the present invention include: an air tightness detection system for a passenger car braking system, including an air pump, a condenser, a dryer, an air pressure sensor, a first solenoid valve, a second solenoid valve, a four-circuit protection valve and a storage One end of the condenser is connected with the air pump, the other end is connected with the drier, one end of the air pressure sensor is connected with the drier, the other end is connected with the air inlet of the first electromagnetic valve, and the air outlet of the first electromagnetic valve is connected To the four-circuit protection valve, the four-circuit protection valve leads to four air storage tanks, and a second electromagnetic valve is arranged between the four-circuit protection valve and the air storage tanks.

Further, both the first solenoid valve and the second solenoid valve are two-position two-way solenoid valves.

The present invention also provides a method for detecting the air tightness of the brake system of a passenger car, comprising

1) Before the air tightness test, the air pump inflates the pipeline, and when the dryer is unloaded, the air pump stops working;

2) Press the "test start" button in the system, the ECU controls the solenoid valve to close, each circuit is independent of each other, and the ECU collects the pressure change within a certain period of time;

3) If the ECU detects that the air pressure of a certain circuit has dropped by more than 110pa within 20s, the red light of this circuit will be on on the display screen, and it is judged that the airtightness is unqualified, and the circuit should be tested separately, the joints should be tightened, and then follow the above Steps to retest this loop until it passes;

4) If the ECU detects that the pressure of all circuits drops below 110pa within 20s, all circuits on the display will light up in green and the vehicle will pass the test.

The invention has the following beneficial effects: the invention can sense the air pressure change of each circuit in the brake pipeline in a short time, and determine whether the vehicle can pass the air tightness test of the whole vehicle according to the reference value of the air pressure drop.

Description of drawings:

Fig. 1 is a structural diagram of the present invention.

Detailed ways:

The present invention will be further described below in conjunction with the accompanying drawings.

As shown in Figure 1, the present invention discloses a passenger car brake system air tightness detection system, including an air pump 1, a condenser 2, a dryer 3, an air pressure sensor 4, a first solenoid valve 51, a second solenoid valve 52, The four-circuit protection valve 6 and the air storage tank 7, one end of the condenser 2 is connected with the air pump 1, the other end is connected with the dryer 3, one end of the air pressure sensor 4 is connected with the dryer 3, and the other end is connected with the inlet of the first solenoid valve 51 The gas ports are connected, and the gas outlet of the first electromagnetic valve 51 leads to the four-circuit protection valve 6 . The four-circuit protection valve 6 leads to four air storage tanks 7 , and a second electromagnetic valve 52 is arranged between the four-circuit protection valve 6 and the air storage tanks 7 .

The air pressure sensor 4 in the present invention is a high-precision pressure sensor, which can sense the change of air pressure in a very short time and transmit it to the ECU. The ECU then determines whether the airtightness of the whole vehicle passes the test according to the pressure drop reference value of the air pressure.

Both the first solenoid valve 51 and the second solenoid valve 52 are normally open two-position two-way solenoid valves, which are opened and closed according to the instructions of the ECU. When the detection is not started, the ECU does not input signals to the first solenoid valve 51 and the second solenoid valve 52 , and the first solenoid valve 51 and the second solenoid valve 52 remain open correspondingly. When the detection starts, the ECU inputs signals to the first solenoid valve 51 and the second solenoid valve 52, the first solenoid valve 51 and the second solenoid valve 52 are correspondingly closed, and the circuits corresponding to the first solenoid valve 51 and the second solenoid valve 52 are independent , so that the air pressure sensor 4 independently detects the pressure of the corresponding circuit. The ECU will receive the signal of the air pressure sensor 4, calculate and compare regularly, and control the opening of the solenoid valve.

The operating principles of the air pump 1, condenser 2, drier 3, four-circuit protection valve 6, and air storage tank 7 in the present invention are the same as those of the air pump, condenser, drier, four-circuit valve in the air braking system of a passenger car in the prior art. The working principles of the circuit protection valve and the air storage tank are the same, so the present invention will not be described in detail.

The detection method of the passenger car brake system air tightness detection system of the present invention is:

1) Before the air tightness test, connect the corresponding air pressure sensor and solenoid valve according to the above connection method; then the air pump 1 inflates the pipeline, and when the dryer 3 is unloaded, the air pump 1 stops working;

2) Press the "detection start" key in the system, the ECU controls the closing of the first solenoid valve 51 and the second solenoid valve 52, and each circuit corresponding to the first solenoid valve 51 and the second solenoid valve 52 is independent of each other; the ECU collects The pressure change within a certain period of time (generally, the pressure drop within 20s does not exceed 110pa) is qualified.

3) If the ECU detects that the air pressure of a certain circuit has dropped by more than 110pa within 20s, the red light of this circuit on the display screen will be on, and it is judged that the air tightness is unqualified; the inspector must test this circuit separately (spray soapy water on the circuit Observe the change of the foam to detect whether there is air leakage) and fasten the joint, and then re-test the circuit according to steps 1) and 2) until it passes;

4) If the ECU detects that the pressure of all circuits drops below 110pa within 20s, all circuits on the display will light up in green and the vehicle will pass the test.

The above is only a preferred embodiment of the present invention, it should be pointed out that for those of ordinary skill in the art, some improvements can also be made without departing from the principle of the present invention, and these improvements should also be regarded as the invention. protected range.

Claims (3)

1. The air tightness detection system 1. a kind of bus brake system is united, it is characterised in that：Including inflating pump (1), condenser (2), dry Device (3), baroceptor (4), the first magnetic valve (51), second solenoid valve (52), four-loop protection valve (6) and gas receiver (7), One end of the condenser (2) is connected with inflating pump (1), and the other end is connected with drier (3), one end of baroceptor (4) It is connected with drier (3), the other end is connected with the air inlet of the first magnetic valve (51), and the gas outlet of the first magnetic valve (51) is led to Four-loop protection valve (6), four-loop protection valve (6) lead to four gas receivers (7), four-loop protection valve (6) and gas receiver (7) it Between be equipped with a second solenoid valve (52).
2. The air tightness detection system 2. bus brake system as claimed in claim 1 is united, it is characterised in that：First magnetic valve (51) and second solenoid valve (52) is 2/2-way magnetic valve.
3. The air-tightness detection method 3. a kind of bus brake system is united, it is characterised in that：Including

   1) before carrying out hermeticity experiment, inflating pump (1) is inflated to pipeline, after drier off-load (3), inflating pump (1) It is stopped；

   2) " detection starts " key in system is pressed, ECU control closed electromagnetic valves, each loop is separate, and ECU collections are certain The change of pressure in time；

   3) if ECU, which is detected, decrease beyond 110pa within certain loop air pressure 20s, this loop sends out a warning on display screen, judges Air-tightness is unqualified, then individually this loop is detected, joint fastening processing, then detect this again according to above-mentioned steps Loop, until passing through；

   4) if ECU, which is detected, descends below 110pa within the pressure 20s in all loops, all loop BGs on display screen Lamp, vehicle passing detection.