Exhibit 23.1 CONSENT OF INDEPENDENT PUBLIC ACCOUNTANTS As independent public accountants, we hereby consent to the incorporation of our reports included in this Form 10-K, into the Company's previously filed Registration Statements on Form S-8 (No. 33-62901, 33-23261, 333-45156) and Form S-3 (No. 333-12781). ARTHUR ANDERSEN LLP Chicago, Illinois June 29, 1998 47