Button with OnClick and value

[NLDeveloper]

<script type="text/javascript">
function recp(id, amount) {   
$('#myStyle').load('join.php?artikelnummer=' + id + '&amount=' + amount); 
} 
</script>  

<form>
<input type="text" name="amount" size="5">
<input type="BUTTON" value="submit" onClick="recp('113', document.amount.value)">
</form>

<div id='myStyle'> </div>

It goes wrong in the Button input part in the Onclick.
The 113 works fine. But how do I get the value out of the textbox in this system?