angularjs socket doesn't disconnect

I have added disconnect function in angular btford.socket-io like this:

disconnect: function() {
      return socket.disconnect();
}

and call it using my socket object.

intervieweeSocket.disconnect();

But when i again create socket connection, nothing happened. I have also tried forceNew parameter in io.connect

mySocket = socketFactory({ioSocket: io.connect(connect_string, {'forceNew':true })});

I am using socket.io version 1.0.6