Regular expression in Laravel

I'm not very good at regex but using the link site I was able to generate an expression that accepts:

• Do not accept special characters
• You can have up to 5 words separated by whitespace

The generated regex: (^\w{0,30}){1}(\s?(\w{0,30})){1,4}

I'm trying to use it in a Request class as a Rule regex

public function rules()
{
    return [

        'name' => 'required|max:255|unique:classes,name|regex:/(^\w{0,30}){1}(\s?(\w{0,30})){1,4}/m',
        'description' => 'max:255',

    ];
}

This is not being validated, anything I enter into the 'name' field the system accepts.