CN105129565B - A kind of brake apparatus fault detection method - Google Patents

Abstract

The invention discloses a fault detection method of a brake device, which comprehensively detects and diagnoses the reliability of the action cooperation between the brake shoe and each sector on the brake drum. Meihua Jianzhu conducts static detection and dynamic detection on the braking device. In the static detection, a torque current in a specific direction is applied to the traction machine when the brake is closed, and the slippage of the traction wheel is observed; in the dynamic detection, Use the sector management unit to formulate the switching sequence between sectors, release the brake and drive the traction machine to rotate, when the traction machine rotates a certain mechanical angle, close the brake and cut off the power supply of the traction machine at the same time, observe the traction machine from rotation Braking distance to stop. By judging the static and dynamic detection results on each sector, the fault condition of the braking device is diagnosed. The invention has a high diagnosis coverage rate, can check out subtle abnormalities of the braking device, prevents minor changes, and effectively prevents failure safety accidents of the braking device.

Description

A method for fault detection of a braking device

technical field

The invention relates to a fault detection method of a braking device.

Background technique

At present, there are many technologies about braking force detection in the domestic industry, but there are certain defects.

For example, in patents 200810094853.0 and 02829758.X, the test can only be carried out on a specific floor, and the resistance test of the elevator is required before the test to determine the test torque of the elevator, which makes the testing process complicated and has many restrictions and low flexibility;

Another example is patent 200810037218.9. This technology applies diagnostic and pre-diagnostic torque to the motor under the braking state, and judges the braking force by detecting the slippage of the car. However, it can only detect the braking force of the braking surface where the brake shoe is located. However, the braking condition of the entire braking device cannot be fully detected. For motor oil leakage, brake drum rust, etc., the inspection rate is low, let alone 100% inspection, leaving potential safety hazards;

Another example is patent 201310705100.X and patent 201180054949.4, both of which require that an increasing torque be applied to the motor under braking until the car slips, and the motor torque when the car slips occurs is compared with a reference value, Thus determine the braking force. However, since the braking force of the brake is far beyond the output torque capacity of the elevator inverter in normal times, in order to realize this technology, a larger-capacity inverter must be selected, so the economic benefit is low.

At the same time, the above technologies still have the following deficiencies: insufficient consideration of the effective mode of braking, such as the oil leakage of the main engine, the oil throwing of the wire rope, and the rusting of the brake drum, so that the local surface of the brake drum is covered with oil, affecting the brake drum. Partial braking force, and in the early stage of the accident, the probability of finding insufficient braking force through the above-mentioned technology is relatively low, so it is impossible to prevent it from happening, and it is easy to leave potential safety hazards and cause safety accidents.

Contents of the invention

Overcoming the shortcomings of the above-mentioned background technology, the present invention provides a brake device fault detection method with high diagnostic coverage, strong practicability, and high economic benefits. In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions:

When the system detects that the elevator door is closed and the car is empty, it can manually or automatically enter the fault detection state of the braking device. In the brake closing state, the system applies a torque current in a specific direction to the traction machine for each detection sector in the brake closed state, and observes the slippage of the traction wheel; in the dynamic detection, the sector manager is used to formulate The switching sequence between them is to release the brake and drive the traction machine to rotate. When the traction machine rotates at a certain mechanical angle, close the brake and cut off the power supply of the traction machine at the same time. Observe the braking distance of the traction machine from rotation to stop. And use this to switch sectors, and diagnose the failure of the braking device by judging the static and dynamic detection results on each sector, and send the failure to the monitoring center.

The brake device fault detection method provided by the present invention can manually or automatically enter the brake device fault detection state when the system detects that the elevator door is closed. In this state, the present invention can use the unique sector management unit to Carry out a comprehensive detection and diagnosis of the reliability of the action cooperation between the brake shoe and the braking surface of each sector of the brake drum. The diagnosis can cover most of the brake failure modes, and it can not only detect common Abnormal movement, brake shoe wear, etc., can also detect rare traction machine oil leakage, brake drum rust and other failure modes, with a high diagnostic coverage. Especially for the situation that there is oil stain on the part of the brake drum, the detection probability is extremely low according to the detection method of the background technology, and it is often not easy to detect until the brake drum is mostly covered with oil stains, but the present invention can achieve comprehensive detection, so it can be done To prevent the incipient progress, to the greatest possible extent prevent the occurrence of safety accidents where the braking device fails. Not only can the reliability test of the action part of the brake device itself be carried out, but also the entire brake drum can be fully tested, and the detection modes are various, including static detection and dynamic detection, especially for the main engine oil leakage, rust, etc. Problems can be prevented in the bud, and problems can be found in advance, which greatly improves the troubleshooting rate of insufficient braking force faults.

Description of drawings

The accompanying drawings described here are used to provide a further understanding of the present invention, constitute a part of the application, and do not constitute an improper limitation of the present invention. In the accompanying drawings:

Fig. 1 is a system block diagram of the present invention;

Among them (a) integrated control system, (b) brake drive unit, (c) variable frequency drive unit, (d) brake, (e) traction machine, (f) rotation detection unit, (g) sector management unit, ( h) Braking device fault detection command;

Fig. 2 is a flow chart of the present invention;

Fig. 3 is an explanatory diagram of situation 1 of the embodiment of the present invention;

Fig. 4 is an explanatory diagram of situation 2 of the embodiment of the present invention;

Fig. 5 is an explanatory diagram of situation 3 of the embodiment of the present invention;

In FIGS. 3 to 5 , (a) brake drum, (b) brake shoe.

detailed description

The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments, where the schematic embodiments and descriptions of the present invention are used to explain the present invention, but not to limit the present invention.

Example:

As shown in Figure 1, the brake device fault detection method of the present invention is realized by the following system: including a variable frequency drive unit, a sector management unit, a brake drive unit, a rotation detection unit, and an integrated control unit, wherein the integrated control unit can drive the brake The unit outputs the command to send the brake open and close, can receive the sector test sequence of the sector management unit, and sends the operation command of the traction machine to the variable frequency drive unit, and the variable frequency drive unit can control the speed of the traction machine according to the command of the integrated control unit. , position and torque control, the sector management unit can diagnose and record the reliability of the cooperation between the brake shoe and each sector on the brake drum, and guide the comprehensive control unit to perform the detection of the sector sequence, The brake driving unit can drive the opening and closing of the brake, and the rotation detection unit can detect the rotation of the traction sheave, preferably a rotary encoder.

As shown in Figure 2, the integrated control unit detects that the elevator hall doors and car doors are closed and the elevator is in an unloaded state. Preferably, the unloaded condition can be detected by a load cell or confirmed by an operator, and the integrated control unit receives After the brake device fault detection command (this command can be entered manually through the man-machine interface, or automatically entered by setting certain conditions), perform the following operations:

1. The integrated control unit judges the position of the car. If it is the top floor, the sector management mode is changed from the default forward direction to the reverse direction. Preferably, the detection of the top floor can be done by checking the state of the upper limit switch in the elevator shaft. detection implementation;

2. Perform static detection, apply a torque of T to the traction machine in the upward direction of the car through the frequency converter, and last for t time, and observe the slip distance L1 of the traction wheel through the rotation detection unit within t time and slip velocity V1, enter step 6, preferably, the rotation detection unit is a rotary encoder;

3. Comparing the slip distance L1 with the threshold Lc, if L1>Lc, the sector management unit records the current sector as unqualified for diagnosis, and performs step (10);

4. Comparing the slip speed V1 with the threshold Vc, if V1>Vc, the sector management unit records the current sector as unqualified for diagnosis, and performs step (10);

5. The sector management unit records the current sector as qualified for diagnosis;

6. After repeating steps (2) to (5) several times, execute step (11);

7. Carry out dynamic detection. When the sector management mode is forward, drive the traction machine to run in the upward direction with a mechanical angle of θ degrees. When the sector management mode is reverse, drive the tractor to run in the downward direction with a mechanical angle of θ degrees. , after running at a mechanical angle of θ degrees, disconnect the power supply of the brake and traction machine through the brake drive unit and the variable frequency drive unit;

8. Observing the braking distance L2 of the traction wheel through the rotation detection unit, and comparing it with the threshold Lc2, if L2>Lc2, the sector management unit records the current sector as unqualified for diagnosis, and performs step (10);

9. Execute step (2);

10. Exit the brake fault detection state, stop the elevator and notify the monitoring center;

11. Exit the brake fault detection state, and release the reliable information of the brake device.

In dynamic detection, the switching between sectors and dynamic detection are integrated into one action mode: through the sector management unit, the switching sequence between sectors is formulated, the brake is released and the traction machine is driven to rotate, when the traction machine rotates At a certain mechanical angle, close the brake and cut off the power supply of the traction machine at the same time, observe the braking distance of the traction machine from rotation to stop, and use this to switch sectors.

In the above-mentioned embodiment, the sector management unit provides operation angle guidance to the integrated control unit through the preset parameters θ and n, so that the brake device fault detection system can completely detect the cooperation between the entire brake drum and the brake shoe situation, where θ is the angle of each rotation of the brake drum, and n is the number of rotations of the brake drum.

The calculation and selection methods of the parameters θ and n are described below for three different situations. For the convenience of explanation, the situation of two brake shoes is used as an example to expand the description:

Case 1: The distribution of brake shoes on the brake drum is symmetrical about the horizontal axis and symmetrical about the vertical axis

This situation is shown in Figure 3. The distribution of the brake shoe on the brake drum is horizontal axis symmetric and vertical axis symmetric, where lp=120°, lm=60°, in order to satisfy It can be seen that when θ=60°, n has a minimum value of n=3, that is, the brake drum rotates 60° each time and rotates twice, and the coordination between the entire brake drum and the brake shoe can be completely detected. The detection angle domain of the area is shown in the following formula:

Situation 2: The brake shoe is continuously distributed on the brake drum

This situation is shown in Figure 4. The distribution of the brake shoe on the brake drum is symmetrical to the horizontal axis, where lp=0°, lm=45°, in order to satisfy It can be seen that when θ=90°, n has a minimum value of n=4, that is, the brake drum rotates 90° each time and rotates 3 times, and the coordination between the entire brake drum and the brake shoe can be completely detected. The detection angle domain of the area is shown in the following formula:

Situation 3: Other situations (that is, situations other than Situation 1 and Situation 2)

Set lp=60°, lm=30°, as shown in FIG. 5 . to satisfy It can be seen that when θ=60°, n has a minimum value of n=6, that is, the brake drum rotates 60° each time and rotates 5 times, and the coordination between the entire brake drum and the brake shoe can be completely detected. The detection angle domain of the area is shown in the following formula:

In summary, by matching to find When the minimum value of n is obtained, the values of the preset parameters θ and n are obtained, among which SQ ₁ ~ SQ _n are calculated by lp, lm, n and θ according to the following formula:

Among them, lp is the minimum angle between the brake shoes on the brake drum, lm is the braking control angle of a single brake shoe on the brake drum, and the sector SQ indicates the angle tested during the static test of the sector scope.

It can be seen from the above that the present invention can completely detect the braking capacity of all sectors, and no matter whether there is oil or rust in any sector, the present invention can detect it in one detection, so as to prevent minor changes and effectively prevent the occurrence of braking force failure accidents .

The technical solutions provided by the embodiments of the present invention have been introduced in detail above, and the principles and implementation modes of the embodiments of the present invention have been explained by using specific examples in this paper. The descriptions of the above embodiments are only applicable to help understand the embodiments of the present invention At the same time, for those of ordinary skill in the art, according to the embodiment of the present invention, there will be changes in the specific implementation and application scope. In summary, the content of this specification should not be construed as limiting the present invention.

Claims (8)

1. A braking device fault detection method, characterized in that: When the door is closed and the car is unloaded, it enters the brake device fault detection state, and performs the following steps until it exits the brake fault detection state: 1) The position of the car is judged by the integrated control unit. If it is the top floor, the sector management mode is changed from the default forward direction to the reverse direction; 2) Perform static detection. The static detection is to apply a torque of T to the traction machine in the upward direction of the car through the frequency converter, and last for t time, and obtain the traction sheave through the rotation detection unit within t time. The slipping distance L1 and slipping speed V1; 3) Comparing the slip distance L1 with the threshold Lc, if L1>Lc, the sector management unit records the current sector as unqualified for diagnosis, and executes step 10); 4) Comparing the slip velocity V1 with the threshold Vc, if V1>Vc, the sector management unit records the current sector as unqualified for diagnosis, and executes step 10); 5) The sector management unit records the current sector as qualified for diagnosis; 6) After repeating steps 2) to 5) several times, execute step 11); 7) Perform dynamic detection. The dynamic detection is that when the sector management mode is forward, drive the traction machine to run in the upward direction at a mechanical angle of θ degrees, and when the sector management mode is reverse, drive the traction machine in the downward direction Run the mechanical angle θ degrees, after running the mechanical angle θ degrees, disconnect the power supply of the brake and the traction machine through the brake drive unit and the variable frequency drive unit, and obtain the braking distance L2 of the traction wheel through the rotation detection unit; 8) Compare the braking distance L2 of the traction wheel with the threshold Lc2, if L2>Lc2, the sector management unit records the current sector as unqualified for diagnosis, and executes step 10); 9) Execute step 2); 10) Exit the brake failure detection state, stop the elevator and notify the monitoring center; 11) Exit the brake fault detection state, and release the reliable information of the brake device. 2. The braking device fault detection method according to claim 1, characterized in that: The sector management unit provides operating angle guidance to the integrated control unit through the preset parameters θ and n, so that the brake device fault detection system can completely detect the cooperation between the entire brake drum and the brake shoe, where θ is The angle of each rotation of the brake drum, n is the number of rotations of the brake drum. 3. The braking device fault detection method according to claim 2, characterized in that: The number of brake shoes is 2; find by matching When the minimum value of n is obtained, the values of the preset parameters θ and n are obtained, among which SQ ₁ ~ SQ _n are calculated by lp, lm, n and θ according to the following formula: Among them, lp is the minimum angle between the brake shoes on the brake drum, lm is the braking control angle of a single brake shoe on the brake drum, and the sector SQ indicates the angle tested during the static test of the sector scope. 4. The braking device fault detection method according to claim 1, characterized in that: The variable frequency drive unit controls the speed, position and torque of the traction machine according to the instructions of the integrated control unit. 5. The braking device fault detection method according to claim 1, characterized in that: The sector management unit can diagnose and record the reliability of cooperation between the brake shoe and each sector on the brake drum, and guide the comprehensive control unit to perform the detection of the sector sequence. 6. The braking device fault detection method according to claim 1, characterized in that: The rotation detection unit is a rotary encoder to detect the rotation of the traction sheave. 7. The braking device fault detection method according to claim 1, characterized in that: The integrated control unit detects the state of the elevator door and the load in the car. When the door is closed and the car is empty, the integrated control unit can receive a command to enter the brake device fault detection state and enter the brake device fault detection state. state. 8. The braking device fault detection method according to claim 1, characterized in that: Switching between sectors and dynamic detection are integrated into one action mode.