你可以参照这个试试
axes: [                          
        {                              
            type: 'Numeric',  //数字类型轴                              
            position: 'left', //停靠位置                             
            fields: ['huoyueyonghushu', 'crmshibaishu'], //Y轴坐标数据,会取最大值                              
            label: {    //轴上数据文本显示  比如label: { rotate: { degrees: 315} } 旋转315°                                  
            renderer: Ext.util.Format.numberRenderer('0')                            },                             
            //title: 'Y坐标',                              
            minimum: 0,  //起始点数 默认0                              
            grid: true  //显示背景表格对照                          
       }