[21] Appl. No.: 111,453

[22] Filed: Jan. 11, 1980

44/7 D; 102/90; 102/363

[56] References Cited
U.S. PATENT DOCUMENTS

Primary Examiner—Edward A. Miller

Attorney, Agent, or Firm—R. S. Sciascia; W. Thom Skeer; Lloyd E. K. Pohl