Consolidated Statement of Operations (USD $)	3 Months Ended		9 Months Ended
	Jan. 31, 2014	Jan. 31, 2013	Jan. 31, 2014	Jan. 31, 2013
Net sales	$ 2,938,000	$ 2,976,000	$ 9,804,000	$ 8,876,000
Cost of goods sold	1,934,000	2,035,000	6,199,000	5,792,000
Gross profit	1,004,000	941,000	3,605,000	3,084,000
Engineering	147,000	129,000	434,000	427,000
Selling, general and administrative	798,000	692,000	2,563,000	1,880,000
Operating Expenses	945,000	821,000	2,997,000	2,307,000
Earnings from operations	59,000	120,000	608,000	777,000
Interest expense, net	8,000	10,000	26,000	32,000
Earnings before provision for income taxes	51,000	110,000	582,000	745,000
Income Tax Expense (Benefit)	20,000	44,000	223,000	298,000
Net Income (Loss) Attributable to Parent	$ 31,000	$ 66,000	$ 359,000	$ 447,000
Earnings Per Share, Basic	$ 0.01	$ 0.01	$ 0.06	$ 0.08