2022 October the Fourth Week GQZ Technical Knowledge: Riveting method of shallow wave cage for deep groove ball bearing
Hot tags: deep groove ball bearing(3)
Abstract: In order to make the deep groove ball bearing replace the cylindrical roller bearing with the same overall dimension, the diameter and quantity of steel balls are increased, and the corresponding shallow wave shaped cage and sheet rivets with special structure are adopted. The design and riveting method of the special riveting die for this series of products are introduced.
Key words: deep groove ball bearing; Shallow wave cage; Sheet rivet; Riveting die
The reinforced (heavy load) deep groove ball bearing newly developed by our company is different from the traditional design of ordinary deep groove ball bearing. It increases the diameter and quantity of steel balls, and there is a ball loading gap on the inner and outer rings of the bearing. In this way, 2~4 more steel balls can be installed than the conventional structure bearing, so the load capacity of the new structure reinforced deep groove ball bearing is equivalent to that of the cylindrical roller bearing with the same overall dimension. Due to the change of the internal structure of the bearing, a shallow wavy cage and a special sheet rivet are used and a special riveting die is trial produced.
1 Technical analysis
Under the same overall dimensions, the new structure bearing can make full use of the internal space, increase the diameter and number of steel balls, so that the gap between the two balls is very small, and it is impossible to rivet with ordinary wave shaped cages and rivets during assembly. Therefore, only shallow wave shaped cages and special structure sheet rivets (Figure 1) can meet the design requirements of high-density balls.
(a) New structure (sheet rivet) (b) Common structure
Fig. 1 Comparison between sheet rivet and ordinary rivet cage
Due to the structural characteristics of this series of products, the plane where the cage rivet holes are located is very small, and the shape of cage rivet holes is rectangular consistent with the rivet head, so it is impossible to rivet according to the conventional riveting method of ordinary deep groove ball bearings. Because the two pieces of cages are not in direct contact, the middle is supported by sheet rivets, and the space between balls. Due to the small gap and the influence of the inner and outer ring rib, the sheet rivets cannot be smoothly inserted into each rectangular rivet hole on the cage of the lower tire. For this reason, technical analysis is carried out, and an efficient and feasible riveting method is developed for the series of heavy-duty deep groove ball bearings.
2 Riveting method
Due to the special structure of this series of products, it is difficult to rivet two pieces of cages at the same time. For this reason, a special riveting die for this series of products was designed, that is, a lower die and a middle die (see Figure 2) were added, and two pieces of cages were riveted in two steps: first, one piece of cage was riveted together with a group of sheet rivets, and then the second step was riveted.
Fig. 2 Riveting of cage with a group of sheet rivets
First, design a special riveting die: on the lower die in step 1, design a groove with the circumference of the cage as the circumference direction and the same width as the rivet head b. See Figure 3 for the rivet structure diagram. The groove depth is the same as the height h of the rivet head. Two protruding locating pins are designed in the middle of the lower die (less than the inner diameter of the cage); The middle die is designed with a rectangular hole with the same number of rivets, the length of the hole is the same as the width B of the nail body, and the width of the hole is the same as that of the nail.The thickness S of the middle die is the same as the height H of the nail body. Two locating holes corresponding to the two projecting locating pins of the lower die are designed in the middle of the middle die. The specific riveting method is:
Fig. 3 Schematic Diagram of Rivet Structure
(1) Step 1 Riveting. Position the lower mold and the middle mold, and then insert the rivet into the equal rectangular hole of the middle mold. The first inserted nail head enters the slot of the lower mold. The height of the nail head is equal to the depth of the slot. The height of the nail body H is the same as the thickness of the middle mold. Only the height of the nail head h is exposed. At this time, place the cage above the middle mold, and the exposed nail heads are inserted into the nail holes of the cage in turn. The contact part between the upper die and the rivet is designed as a platform. A group of rivets and a piece of cage are riveted into an assembly (Figure 4) through impact pressure to complete the first step of riveting.
Fig. 4 Cage assembly
(2) Step 2 Riveting. Place the closed ferrule and steel ball on the cage and a group of rivets assembly according to the conventional method (Fig. 5). Put another shallow corrugated cage on it, and insert the pin holes of the cage into each pin head in turn; Then, put it into the riveting die (at this time, the difference between the riveting die and the conventional riveting die is that the upper and lower die pin sockets are changed from round sockets to flat ones), and complete the whole riveting through the impact pressure.
Fig. 5 Step 2 Riveting
Riveting of reinforced heavy-duty deep groove ball bearing series products: first, two special riveting dies, the lower die and the middle die, need to be designed. Then, first, complete the riveting of a group of rivets and a piece of cage assembly, and then use the special riveting die to rivet according to the conventional method. This method is advanced and feasible, which ensures the product quality and improves the assembly efficiency.
More about GQZ deep groove ball bearing:
Deep groove ball bearings are the most widely used bearing type and have the most comprehensive functions. This bearing features low friction, optimized for low noise and vibration, enabling high rotational speeds. It can withstand radial loads and axial loads in both directions, and is easy to install and requires less maintenance than other types of bearings.
Deep groove ball bearings are the most widely used type of bearings and are suitable for a variety of industries. This bearing is available in a variety of designs, variants and sizes to meet a wide variety of application needs. The applications of deep groove ball bearings are as follows:
Motors and Generators
food and drink
Two- and three-wheeled vehicles
Cars and Light Trucks