var objXL = WScript.CreateObject("Excel.Application");
objXL.Visible = true;

var xlNormal = -4143;
var xlMaximized = -4137;
var xlMinimized = -4140;

objXL.Left = 0;
objXL.Top = 0;
objXL.Width = 600;
objXL.Height = 500;
objXL.WindowState = xlMaximized;	//最大化
objXL.WindowState = xlNormal;		//元の大きさに
objXL.WindowState = xlMinimized;	//最小化