2022 December the Third Week GQZ Technical Knowledge: Principle and structure of one-way bearing
Hot tags: deep groove ball bearing(4)
One way bearing is a kind of bearing that can rotate freely in one direction and is locked in the other direction.
The metal shell of a one-way bearing contains many rollers, needles or balls, and the shape of its rolling seat allows it to roll only in one direction, while it will produce great resistance in the other direction (the so-called "one-way").
1. Working principle of one-way bearing
In fact, the principle of one-way bearings of any structure is the clamping principle, which can be divided into:
Ramp and roller type:
Here, the outer ring of the bearing is the same as the ordinary bearing, which is a cylindrical outer ring. However, its inner circle structure is special. Its inner circle is a circle with a slope.
In addition, it is composed of rollers that are always in contact with the inner and outer rings and springs that are in contact with the rollers. The working surface of the roller is a slope. When the bearing rotates along the slope, the roller is in a downhill state. The downhill space is large, and the roller will not be affected.
When the roller rotates in reverse direction, it is uphill. The uphill is narrow, the roller is stuck, and the bearing is locked.
Another structure of one-way bearing is wedge structure:
A group of cam wedges will be set between the inner ring and outer ring of this type of bearing. The cam has two diameters of different sizes. The long diameter is larger than the distance between the inner race and the outer race, while the short diameter is smaller than the distance between the bearing inner race and the outer race.
Between the wedges, a cylindrical winding spring is connected end to end to form a ring spring, which is set on the fulcrum of the wedges. The wedges can be reset by the action of the spring.
2. Installation of one-way bearing
As the one-way bearing has been treated with rust prevention and packaged, do not open the package until the temporary installation. The anti rust oil coated on the one-way bearing has good lubrication performance. For the one-way bearing for general use or the one-way bearing filled with lubricating grease, it can be used directly without cleaning.
The installation method of one-way bearing varies according to the bearing type and matching conditions.
Generally, the inner ring and outer ring can adopt interference fit and clearance fit respectively due to shaft rotation. When the outer ring rotates, the outer ring adopts interference fit.
(1) Press in installation
Press in installation generally uses a press, or bolts and nuts, or a hammer if necessary.
(2) Heat jacket installation
The heat sleeve method of heating the one-way bearing in oil to expand it and then installing it on the shaft can avoid unnecessary external force and complete the installation in a short time.
As an aside, some models in the catalog of one-way bearings do exist, but some non-standard one-way bearings are not available in stock in Chinese Mainland, and sometimes futures will take a long time, so time cost and later replacement cost should be considered when selecting one-way bearings.
3. Overhaul and maintenance of one-way bearing
Generally, the maintenance of one-way bearings requires several steps, including:
(1) Look
The check of one-way bearing is to check whether the one-way bearing is rusted, cracked and peeled.
(2) Listen
Listen to whether the one-way bearing has noise and whether the one-way bearing noise is normal.
(3) Diagnosis
Use instruments for diagnosis, such as electronic diagnostic apparatus, stethoscope, etc.
The maintenance work of other bearings is much the same as that of other bearings. The relative movement of rolling elements and raceways and the invasion of pollutants and dust make the surfaces of rolling elements and raceways worn. The accuracy of the host is affected.
When checking or replacing parts regularly, it is necessary to remove the one-way bearing. Generally, almost all shafts and bearing housings will continue to be used, and one-way bearings will also continue to be used. Therefore, the structural design shall consider that the bearing, shaft, bearing box and other parts shall not be damaged when disassembling the bearing, and proper disassembly tools shall be prepared at the same time. When disassembling the ferrule with static fit, the tension can only be applied to the ferrule, and the ferrule shall not be drawn through the rolling element.
One way bearings are widely used in textile machinery; Printing machinery; Automobile industry; Household Electric Appliances; Currency Detector.
The invention of one-way bearing solves many problems of mechanism that need to prevent reverse rotation. It has played a great role in many household appliances, such as washing machines. It can effectively prevent materials from falling back in some conveying machinery, such as material transportation.
Therefore, the standardized structure makes many machines no longer need to design special anti reverse structures separately, saving a lot of manpower and material resources, so the development prospect of one-way bearings is very broad.
More about GQZ Deep Groove Ball Bearing:
Deep groove ball bearing is one of the most widely used rolling bearings. It is characterized by low friction resistance and high speed. It can be used for parts bearing radial load or combined load of radial and axial at the same time. It can also be used for parts bearing axial load, such as small power motor, automobile and tractor gearbox, machine tool gearbox, general machines, tools, etc.
Features of deep groove ball bearing:
1.Each groove of the bearing has a circumference of about 1/3 of the continuous groove. It is mainly used to bear radial load and certain axial load.
2. when the radial clearance of the bearing increases, it has the property of angular contact ball bearing and can bear the alternating axial load in two directions.
3. low friction and high speed.
4. simple structure, low manufacturing cost and easy to achieve high manufacturing accuracy.
5. generally, stamping wave cage is adopted. For bearings with inner diameter greater than 200mm or high-speed operation, turning solid cage is adopted.
There are more than 60 variant structures of deep groove ball bearings.
Founded in 1999, Wuxi Guangqiang Bearing Trade Co.,LTD, deals with precision bearings and bearing related products across a large spectrum of customers. Since the founding the company, we keep standing by the principle of "Quality First, Credit First, Independent Innovation" and our company has won a great reputation from home and abroad.
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