Elevator brake repair and maintenance process - Solutions - Huaqiang Electronic Network

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1. Brake safety technical inspection;
(1) Strengthen the maintenance and maintenance of the main spring to ensure the braking force. When the inspection, the brake shoe is first closed, and then the brake device is opened by the release device. The hand can sense whether the spring is soft or not. The hammer strikes the spring and checks for spring failure and cracks with sound.
(2) Whether all components are operating normally or not, and there is no jam. Lubricate all the spliced ​​parts once a week, and add 10# gasoline to the active part. Note that the oil cannot drip onto the brake wheel and brake band.
(3) Whether the brake shoes are attached to the brake wheel, and whether the brake shoes at both ends of the brake shoe are separated from the brake shoe body.
(4)Whether the surface quality of the brake wheel is good, and the adjustment nut and lock nut are loose or not.
2. Check points:
(1) The brake must be flexible. **The brake shoe should be closely attached to the working surface of the brake wheel. The newly replaced brake belt requires that the contact surface between the brake belt and the brake wheel is not less than 80% of the brake belt area. The method: measuring by the circle method (also called the surrounding measurement method or the eight-point measurement method), when the brake is released, the brake shoe leaves the brake wheel at the same time, there is no local friction, and in the emergency dialing, the sliding distance of the elevator is operated according to the operation. The speed of 0.5m / s calculation should not be 100mm.
(2) The electromagnetic coil joint should be free from looseness, and the outside of the coil should have good insulation protection to prevent short circuit. When the DC electromagnetic brake is released, the economical resistance is connected to the coil circuit through the normally closed contact of the contactor, so that the temperature rise is reduced. The voltage at both ends of the coil is 110V during normal starting, and the series resistance is 55±5V. Do not exceed 60 °C.
(3) The pin of the brake can move freely. It can be lubricated with thin oil. When the pin wear amount exceeds 5% of the original diameter or the ellipticity exceeds 0.5mm, the new shaft should be replaced. The cracks and springs should be replaced in time.
(4) The iron core of the elevator iron can be slidably flexed in the copper sleeve, and if necessary, it can be lubricated with graphite powder (can be replaced by pencil core powder).
(5) The brake band should be free of greasy or paint to prevent excessive braking slip. Reduce the braking torque with a small knife or kerosene. The rivet of the fixed brake belt shall be buried in the hole of the countersunk seat. The rivet head of the new brake belt shall sink to a depth of not less than 3 mm. At any time, the rivet head of the brake belt shall not be in contact with the brake wheel, and the brake belt may wear up to the original thickness of 4 A new belt should be replaced when /1.
(6) In order to ensure uniform gap between the upper and lower ends of the brake shoe and the brake wheel, and the force applied on the entire contact surface is uniform, the brake base must be adjusted with the gasket to keep the brake shoe and the center line of the brake wheel horizontal. And meet the requirements of center height and straightness. When checking, pay attention to whether the anchor bolt is rotated and whether the gasket is displaced.
(7) Check the reliability of the loose-brake device in the same way as the adjustment method.
(8) Check the gap between the two cores and measure the different lengths of the bolts in the release and braking states.
(9) The surface of the brake wheel should be free of high-temperature coking particles without scratches, otherwise it should be smoothed.
3. Brake adjustment:
(1) Adjustment of electromagnetic force.
In order to make the brake have sufficient release force, the gap between the two cores must be adjusted.
Use the wrench to loosen the compression nut on the adjusting nut, adjust the clearance of the adjusting nut, and tighten the compression nut.
In the coarse adjustment, the adjusting nuts on both sides should be screwed in, so that the two cores are completely closed, and the exposed lengths of the bolts are measured and made equal.
The coarse adjustment is made, and one side is selected to withdraw 0.3mm as the adjustment. The tightening nut no longer moves it, and the other side carefully withdraws the adjusting nut, so that the sum of the two side bolts is 0.5~1mm, that is, the gap between the two cores is 0.5. ~1mm. After the bolt is retracted, it can be measured with a watch.
(2) The braking torque is generated by the spring, and the compression of the main spring must be adjusted. The method is as follows: loosen the main spring compression nut, (the brake belt part) tighten the adjusted nut to reduce the spring length and increase the elastic force to make the brake If the torque is large or screwed out, increase the length of the spring to reduce the spring force, so that the braking torque is small. After the adjustment, tighten the compression nut.
Adjustment notes:
1) The length of the main springs on both sides should be equal and adjusted.
2) Satisfy the car to provide sufficient braking force to force the car to stop running quickly and be reliably at rest.
3) Satisfy that the car should not be too fast and too fast during braking, keep the brakes stable, and achieve smooth and rapid braking, so the braking torque should not be too large.
4) If the braking torque is too small, the rapid stoppage will affect the leveling accuracy, and even the pulley phenomenon or the anti-flat layer will appear.
5) The brakes are used for a long time. Especially in the initial stage of use, the wear speed is very fast. After the brake belt and the brake wheel are worn in, the wear is slowed down. Due to the wear of the brake belt, the main spring will gradually reduce the dynamic torque. For the convenience of adjustment, it is better to mark the length of the spring on the double-headed screw after the brake is installed and adjusted. When the brake belt wear spring is extended, the spring can be adjusted back to the original length according to the reticle to ensure that the dynamic torque does not change.
(3) Adjustment of brake shoe and brake wheel clearance
1) The brake shoe should be evenly spaced from the brake wheel, and the clearance of any part should be within 0.7mm.
2) Adjustment method:
Use the manual brake to release the brake shoe. At this time, the two iron cores are closed together, screw the upper two screws into or out, and check the clearance between the upper, middle and lower positions of the brake wheel of the brake shoe with a feeler gauge. Should be equal. With the stopper inserted into the gap 2/3, both brake dams should be inspected, and the measured values ​​should be as consistent as possible. If properly adjusted, the gap between the brake dam and the brake wheel is adjusted to 0.45~0.5mm.
(4) Adjusting and repairing the elevator, checking the motor, adjusting the brake pad clearance, releasing the safety gear, stopping the car, resetting the car, and stopping the car, etc. watt. The method is as follows: the double-headed screw is rotated by 90° with a wrench, and the inclined surface of the cam fixed on the double-headed screw pushes the brake arm outward, the brake arm rotates around the fulcrum, and the brake dam leaves the brake wheel, and the release operation is completed. .
The method of resetting is to rotate the double-headed screw 90° in the opposite direction, and the inclined surface is re-fitted under the action of the main spring, and the brake is restored to the original state.