If a dryer has a short in it that causes the circuit breaker to trip, it will usually trip the circuit breaker as soon as the dryer is started.
When a circuit breaker trips after the dryer has been running for a few minutes, the problem is usually in the circuit breaker or the house wiring connections. The breakers should have a 30 amp rating.
Try a cycle on the dryer (Air Fluff) that does not use the heat element to come on. If the dryer runs, the fault is probably a short in the heat element. With breaker off and machine unplugged, you could also check all wired connections for loose,dirty/corrosion/burnt/damage in dryer including dryers terminal block and the supply box/receptacle that dryer plugs into.
You can find parts here: searspartsdirect.com/model/1w645tfomb-000582/kenmore-41793142202-dryer-parts
More help: searspartsdirect.com/diy/symptom/dryer-repair/1234594/starts-then-stops/dryel09
If you'd like a professional repair, call Sears Home Services at 1-800-4-MY-HOME.