Why automobile brake drum two lining differ long brake lining and brake drum gap is too big
Why automobile brake drum two differ long brake lining and brake drum of lining clearance is too large. When the vehicle in the process of moving to slow down or even stop, must be installed on the vehicle braking device, so that the driver can according to the road and traffic control and vehicle brake, to slow down or stop a moving vehicle in order to ensure driving safety. In the known brake used in most of the brake using fixed friction on the surface of the components of rotating components work to generate the braking torque, this is called the friction brake. Why automobile brake drum two friction piece inside the long range due to the wheel brake brake shoe ( Such as led, from the hoofs) The pressure ( The pressure) Different ( As Beijing 2020 s before and after the rear wheel brake brake shoe, FIG. 2 8) If two brake shoe lining size, Area of the same) , to bring pressure on the hoof is strong, wear quickly. From the foot pressure is small, wear more slowly. To make the two brake shoe is close to life (such as Need to change with the change) , most of the auto makers are often the brake shoe pressure is bigger, Such as when the car forward led hoof left foot) Circumferential size is larger, and the smaller the brake shoe is often pressure ( Such as when the car forward from hoof of the right shoe) Weeks to do the smaller size, the two pressure on the brake shoe is close to equal. Brake friction disc and the brake drum clearance is too large when maintenance know the wheel brake pressure type, are often faced with brake lining and brake drum between the gap is too big, can't use the method of adjusting the recovery, and lower the braking efficiency. But the brake lining wear is not too big, still can continue to use. Encounter this situation, usually adopt replacement brake friction plate or on the brake shoe end for brake shoe with 'tin box' ( Commonly known as for brake shoe 'shoes') 。 The previous methods appear waste; The latter method is not the best policy, because it fit up on the hoof, drum gap adjustment will bring some inconvenience. Below is the way an ideal solution. Its particular way is: the original brake lining rivets with bit drilling; Choose the thickness of 0. 50 ~ 1. 00 mm asbestos board, according to the shape of the brake lining, back to the good size processing, and a hole drilled rivet; Will be asbestos board pad between brake shoe and lining, and the three tightly with rivet riveted together. To make its arc as part of the circle, also can be processed by this method a pair of brake shoe on the brake shoe cutting machine for turning processing. After loading, can easily adjust the brake hoof, drum gap. Car wheel brake drum brake friction disc and clearance adjustment, can be adjusted according to the need of local and overall. Partial adjustment: brake slack adjuster is used to change the original position of brake CAM. On both sides of brake slack adjuster shaft body and cover within the cavity is surrounded with adjustment of worm gear and worm. The adjustment of the single worm on the worm shaft spline set. Adjust the worm gear spline spline and brake camshaft within. , turning worm wheel brake slack adjuster and the brake chamber pushrod under the condition of the relative position of the same, make through worm gear brake camshaft turned a certain Angle, so as to change the original position of brake CAM shaft. Worm shaft and the relative position of brake slack adjuster is fixed by locking sleeve and locking screws. Will have hexagonal hole of lock set press into the hole of the brake slack adjuster body, can adjust the worm rotation. Worm every week six points, put the lock set, spring is about to lock up set back and the worm hex head joint left limit position. To conduct a comprehensive adjustment, rotation with eccentric shaft neck at the same time the brake shoe underwriting, with 2. 5 second eccentricity. In replacement of brake shoe lining, reprocessed after the friction surface of brake drum or due to remove the backing plate CAM brake underwriting the rotation and position change, undermining the drum brake friction plate and correct contact state, the need for comprehensive adjustment. Comprehensive adjustment order: first, remove the review of the brake drum cover, loosen the brake shoe of underwriting fixed nut and camshaft bracket fastening bolt nut, then turn the brake shoe eccentric underwriting, make two eccentric supporting pin end tag itself relatively; Iterate through the budge slack adjusters brake branch underwriting and worm shaft, make the drum brake friction disc and fully fit, in this position carefully adjusted fixed nut and tighten the stents brake shoe bearing lock nut, finally will worm shaft loosen 3 a 4 ring, brake drum should be free to turn, and not with the brake shoe friction slices or brushed against other parts. At this time of the gap between drum brake friction disc and scope is: the underwriting side 0. 25 a 0. 40 mm, CAM port 0. A 40 O. 55 mm, end with the difference between the two shoes should not be greater than zero. 1mm。 In addition, the brake shoe lining after wear, brake chamber pushrod schedule if more than 4 mm, in order to reduce the clearance between the brake drum and brake shoe friction piece, should be partially adjusted ( At this time can't turn the underwriting, lest destroy the original contact good condition) 。 Local adjustment, face slack adjuster screw, the front two worm for tight turn clockwise, counterclockwise turn worm as the pine; The rear wheels of the two screw clockwise to move worm is loose, screw counterclockwise is tight.