Inventories (Tables)

3 Months Ended

Jul. 31, 2013

Inventories [Abstract]

Schedule of Inventory, Current [Table Text Block]

	July 31, 2013		April 30, 2013
Raw materials	$	961,000	$	850,000
Work in process	316,000		281,000
Finished goods	195,000		260,000
	$	1,472,000	$	1,391,000