Braking means for shopping cart
US5664645A · kind A · utility
Inventor
Key dates
| Filing date | Aug 22, 1996 |
| Grant date | Sep 9, 1997 |
| Priority date | — |
| Expiry date | Aug 22, 2016 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB62B5/0466
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
A shopping cart has automatically applied brakes when the cart is at rest. The braking for the cart is by rotating the two casters to be non-parallel to each other so the cart will not roll. Any structure for rotating the casters may be used, but the preferred embodiment has an undulating upper bearing race so the weight of the cart urges the upper race down and causes the balls to seek high points on the upper race. The balls are caged, and the cage is fixed to the lower race, so the wheels of the casters are rotated when the balls enter the high areas. The upper bearing races are oriented to achieve the desired positioning of the caster wheels.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.