Integrate my Classes into CodeIgniter

Hello,

Iam new in the "Codeigniter World".

Im still working at my first "real" Project with CodeIgniter and I Like to add some "Entity" Classes for my Project.
But Iam not sure whats the right way to do that in CodeIgniter.

Here is a Sample Class:

PHP Code:

class UserPayment {

    /**
     * @var $id int
     */
    private $id;

    /**
     * @var $userId int
     */
    private $userId;

    /**
     * @var $iban String
     */
    private $iban;

    /**
     * @var $bic String
     */
    private $bic;

    function __construct(
        $id,
        $userId,
        $iban,
        $bic
    )
    {
        $this->id = $id;
        $this->userId = $userId;
        $this->iban = $iban;
        $this->bic = $bic;
    }
} 


I hope you know what I mean.
Sorry for my English

Greats!