US 5,242,224 A · Temperature monitoring unit

Abstract

A temperature monitoring unit has a high degree of sensitivity and reliability even when monitoring the temperature of a relatively large rotary heating element. The temperature monitoring unit includes a mirror which is provided in the vicinity of the rotary heating element and is oriented to reflect infrared rays from the heating element in the radial direction thereof, the mirror being reciprocated linearly in the radial direction, a condenser lens provided radially outwardly of the heating element for converging the infrared rays reflected by the mirror, an infrared sensor on which the converged rays impinge, a plate provided between the mirror and the lens and which has a slit therein that is elongate in a direction approximately perpendicular to the surface of the heating element, and an image processor receiving the output of the infrared sensor. The sensitivity is high because infrared rays from around the thermal point of the heating element are blocked by the plate. Moreover, because the visual field is elongate in the radial direction of the heating element, the mirror can quickly scan the entirety of the heating element.

Claims11

Dependent claims

A temperature monitoring unit for monitoring the temperature of a surface of a rotary heating element, said monitoring unit comprising:

an infrared sensor disposed radially outwardly of the rotary heating element;
and
optical transmitting means for transmitting light to said infrared sensor from only a generally rectangular visual field on the surface of the heating element, longer sides of the rectangular visual field extending in the radial direction of said rotary heating element, and for scanning the surface of rotary heating element in said radial direction such that the rectangular visual field from which light is transmitted from the surface of the rotary heating element to the infrared sensor is moved across the surface of the rotary heating element in said radial direction,
said optical transmitting means including a mirror oriented to reflect light from the surface of the rotary heating element toward the infrared sensor, drive means connected to said mirror for reciprocating said mirror linearly in said radial direction of the heating element, and a plate interposed between said mirror and said infrared sensor, said plate having a generally rectangular slit extending therethrough, longer sides of said slit lying in planes extending perpendicular to the surface of said rotary heating element.

1 more element

A temperature monitoring unit for monitoring the temperature of a surface of a rotary heating element, said monitoring unit comprising:

an infrared sensor disposed radially outwardly of the rotary heating element;
and
optical transmitting means for transmitting light to said infrared sensor from only a generally rectangular visual field on the surface of the heating element, longer sides of the rectangular visual field extending in the radial direction of said rotary heating element, and for scanning the surface of rotary heating element in said radial direction such that the rectangular visual field from which light is transmitted from the the surface of the rotary heating element to the infrared sensor is moved across the surface of the rotary heating element in said radial direction,
said optical transmitting means including a mirror oriented to reflect light from the surface of the rotary heating element toward the infrared sensor, drive means connected to said mirror for reciprocating said mirror linearly in said radial direction of the heating element, and a lens interposed between said mirror and said infrared sensor, said lens having a generally rectangular shape, shorter sides of said lens extending generally parallel to the surface of the heating element.

1 more element

Dependencies are inferred from the claim text.

Temperature monitoring unit

Life of this patent

Temperature monitoring unit

Life of this patent

Abstract

Claims11