05332539 cites 13 patents.

An apparatus for indirectly measuring relatively long, linear distances associated with the operation of an injection molding machine. In particular, the method and apparatus of the present invention can be used to determine the distance between two machine components or systems that are capable of relative (linear) movement. The apparatus includes a rigid bar that extends over the distance traversed by the components of interest, the bar being oriented at a slight angle relative to the line of movement. Immediately adjacent the bar is a sensing element capable of accurately determining the relatively short distance between the sensor and the bar. It is contemplated that the bar would be associated with one of the machine components and the sensor connected to the other. Given that there is only linear movement between the components, the distance between the sensor and the bar will be proportional to the distance between the two machine components. A simple calculation based on the angle of the bar and the distance from the sensor to the bar determines the corresponding separation of the two parts.

Title
Non-contact linear position transducer for an injection molding machine and method of using
Application Number
8/37758
Publication Number
5332539
Application Date
March 26, 1993
Publication Date
July 26, 1994
Inventor
Ronald M Sparer
Madeira
OH, US
Agent
Stephen H Friskney
Assignee
Cincinnati Milacron
OH, US
IPC
B29C 45/80
B29C 45/04
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