JS实现每隔一段时间数量增加或减少

<div class="minge">
    <p>仅剩 <span>126</span>个名额</p>
</div>

数据增加的js:

<script type="text/javascript">
$(function(){
    numPlus($(".minge span"),3000)    
})

var numPlus = function(obj,time){
    setInterval(function(){
        if($(obj).html()==0){
            return;
        }
        $(obj).html(parseInt($(obj).html())+1)
    },time)
}

</script>