Anytime I've make wine using fruit I've had to "punch the cap" down several times a day. Most recently I was using grapes and was punching the cap down 4 times a day for the first few days and 3 times a day there after until fermentation was complete (~7 days for total fermentation). The object is to keep the fruit wet and loose in the juice solution so the yeast can consume it and so bad stuff doesn't grow on it, not to pulverize the fruit.