Maatwebsite - Excel导出在Laravel中不起作用

I use maatwebsite for to Export Report as Excel Format. when i export minimum records its downloaded properly, but more than 70 records its display html page not download.

here is my coding :

Excel::create('InsQuote', function($excel) use ($bDtaa) {

            $excel->sheet('New sheet', function($sheet) use ($bDtaa) {

                $sheet->loadView('export.insquote',compact('bDtaa'));

            });

        })->export('xls');