I found the following at the
United States Patent Office Archive.
---------Excerpts Of Patent #5,787,892---------
Abstract
A device for determining the contractions of an anal sphincter and associated muscles comprising a core formed in a generally cylindrical configuration from a relatively rigid plastic material having a distal end and a proximal end, the core having a central section of a reduced diameter and an axial length, sheet material formed of a flexible essentially inelastic plastic material with an adhesive securing the sheet material to the core and a head adjacent to the distal end of the core, the proximal end of the head being located adjacent to the distal end of the central section and with the distal end of the head being of a reduced diameter.
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1. An anal orgasm monitor for determining the contractions of an anal sphincter and associated muscles during an orgasm and sexual arousal, comprising, in combination:
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a water inlet tube having a proximal end remote from the core and a distal end coupled to the first axial aperture;
an air outlet tube having a proximal end remote from the core and a distal end coupled to the second axial aperture for allowing the removal of air from the region of the core adjacent to the sheet;
a transducer coupled to the proximal end of the water inlet tube with an associated fill tube and inlet valve to allow the selective adding of water to the inlet tube and core and the calibration of the transducer to atmospheric pressure;
an outlet valve at the proximal end of the air outlet tube to allow the escape of air from the core and associated tubes during the filling of the core with water and for closing off the air outlet tube when the tubes and core are full of water; and an electronic monitor coupled to the transducer whereby pressure variations on the central section as caused by an anal sphincter during orgasm will provide a display of variations in pressure sensed by the central section of the core.
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2. A device for determining the contractions of a muscle comprising:
a core formed in a generally cylindrical configuration from a relatively rigid plastic material having a distal end and a proximal end, the core having a central section of a reduced diameter and an axial length, the core having a water inlet and air outlet;
sheet material formed of a flexible essentially inelastic plastic material with an adhesive securing the sheet material to the core; and
a head adjacent to the distal end of the core, the proximal end of the head being located adjacent to the distal end of the central section and with the distal end of the head being of a reduced diameter.
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