Inventories (Tables)

6 Months Ended

Oct. 31, 2014

Inventories [Abstract]

Schedule of Inventory, Current [Table Text Block]

	October 31, 2014		April 30, 2014
Raw materials	$	1,162,000	$	955,000
Work in process	538,000		261,000
Finished goods	325,000		239,000
	$	2,025,000	$	1,455,000