Codeigniter Cookie不起作用

Im using codeigniter 2.2.0 , I want to set cookie and get it in another contoller ! but it does not get cookie !! I set in autoload.php :

$autoload['helper'] = array('url','cookie');

my code in controller/welcom.php :

class Welcome extends CI_Controller {
    public function index()
    {
            $cookie = array(
            'name'   => 'hello',
            'value'  => 'Im content for soheil',
            'expire' => 3600
        );
        $this->input->set_cookie($cookie);
    }
}

anfd before that I set in config/config.php this values :

$config['cookie_prefix']    = "";
$config['cookie_domain']    = "localhost";
$config['cookie_path']      = "/ci2.2/"; 
$config['cookie_secure']    = TRUE;

for localhost and /ci2.2/ : I've create a normal php cookie and in firefox I found this information for it ! while I have tested it whith this code :

$config['cookie_prefix']    = "";
$config['cookie_domain']    = "";
$config['cookie_path']      = ""; 
$config['cookie_secure']    = TRUE;

afterI open welcome page I can see that the cookie has been created i firefox cookies , but when I want to get it by this code in another conroller by this code :

class Soheil extends CI_Controller {

    public function index()
    {
        echo 'coolie is : '.$this->input->cookie('hello');
    }
}

it returns NULL while I see the cookie is seted in firefox :

name : hello 
Content : Im content for soheil
Path :/ci2.2/
send for : Encrypted connections only
expires :Saturday, March 21, 2015 11:44:00 PM

I have read this questions : Why doesn't cookie work in CodeIgniter? - Setting cookies not working in CodeIgniter - Cookie not working with Login System CodeIgniter

but still I have my problem