Rotary pump with bearing wear indicator

A rotary pump for liquid having a housing, a shaft carrying a motor rotor, a motor stator fixed in said housing and surrounding said rotor to rotate said rotor and shaft about an axis, said shaft being mounted in said housing by axially spaced conical bearings, each bearing including a first element fixed on said shaft with a first conical bearing surface concentric with said axis, a coacting second element carried by said housing with a second conical bearing surface concentric with said axis and slidably engaging said first bearing surface and a spring forcing said elements together, said pump including a wear indicator comprising:

• a cage attached to and movable axially with a second element of a bearing as said bearing surfaces wear, said cage surrounding said shaft and carrying an imbalance plate with an outer portion supported on said cage for free rotation in said cage and an inner portion surrounding but normally spaced from said shaft, a first drive member fixed on said shaft and a second drive member on said plate and axially aligned with said first drive member so said members engage when said cage moves axially a given distance whereby said imbalance plate is rotated in said cage by said shaft.