Edward T Heck

US Patent:

52939006, Mar 15, 1994

Filed:

Sep 30, 1992

Appl. No.:

7/954555

Inventors:

Hassan Karbassi - Hartland WI
Edward T. Heck - Waukesha WI

Assignee:

Hydro Electronic Devices Inc. (HED) - Hartland WI

International Classification:

F16K 3700

US Classification:

137554

Abstract:

A direct drive joystick has a contactless system for sensing the position of the joystick lever and having valve drivers which are positioned within the joystick, and which are directly connected to coils of a proportional valve. The joystick thus is not prone to failure due to internal friction of its sensing elements and at the same time is capable of directly driving valves without the provision of any other devices between the joystick and the valves. The joystick including the valve driver is rugged, compact and can be easily installed. The valve driver can be adjusted by an operator who is simultaneously actuating the joystick. The operational status of one or more of the joystick, the valve being controlled by the joystick, and the power source for the valve and joystick are visually displayed at a location which can be easily viewed by the joystick operator. Operation of the valve driver and thus of the joystick is prevented upon failure of a signal wire or upon generation of a joystick fault signal.