Spinning self-latching ball strainer is based on inverted V type ball strainer. It has radically changed the actuating way to 4 bar mechanism. This design has much more advantages than any other kinds of ball strainers as follows:

1. The designed freedom degree of the mechanism is 1, equal to the number of driving links. So when the crank makes rotary movement around a fixed axis according to an independent movement discipline, the linkage drives the screen plate to spin between the two limiting position on the left and right within the stated spinning angle. It’s reliable to realize the collecting and backwashing conditions.

2. When the screen plate spins to the left limiting position, it is under collecting conditions and the ball is out from the bottom; while the screen plate spins to the right limiting position, it’s under backwashing conditions and the plate parallels the water flow, thus backwashing the plate and reducing water resistance. 

3. The crank and the linkage in the two limiting positions are in collineation and it is the middle gear of the mechanism, which can be used for self-latching. At this time, no matter how much force effect on the screen plate, its unchanged position realizes the ball collecting and backwashing function.