Tmytimer = class(TThread)
    private
      myTimer: TTimer;
    public
     constructor Create;
     procedure execute; override;
     procedure timerevent(Sender: TObject);
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

constructor TmyTimer.Create;
begin
  inherited Create(False);
  FreeOnTerminate:=True;
  myTimer:=TTimer.Create(nil);
  myTimer.Interval:=1000;
  myTimer.OnTimer:=timerEvent;
  myTimer.Enabled:=True;
end;

procedure Tmytimer.timerevent(Sender: TObject);
begin
  beep;
end;

procedure Tmytimer.execute;
begin
while not Terminated do
  sleep(10);
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
 tmytimer.Create;
end;