Method and apparatus for calibrating thermometers and the like

Claim 2

That method of providing a transparent tubular member partially charged with a column of liquid with a scale for determining the position of the column which comprises: automatically advancing a plurality of said tubular members in succession to an inspection station, employing electrically responsive sensor means to scan an individual tubular member when in position at said inspection station to determine the position of one end of the liquid column lengthwise of said member, and placing a scale upon the exterior of each tubular member with a predetermined reference point on the scale directly opposite the end of said liquid column.

Claim 3

That method defined in claim 1 characterized in the step of utilizing a light beam in combination with photoelectric detector means to perform said scanning step.

Claim 4

That method defined in claim 1 characterized in the step of carrying out successive scanning and scale-placing operations automatically in predetermined timed sequence.

Claim 5

That method defined in claim 1 characterized in the step of stabilizing the temperature of said tubular members and the liquid contents thereof at a predetermined temperature preselected to correspond with the location of the predetermined reference point for the placement of said scale.

Claim 6

That method defined in claim 1 characterized in the stop of beginning successive ones of said scanning operations from a predetermined starting position known to be normally spaced from the end of liquid column despite variations in manufacturing tolerances between a multiplicity of said tubular members.

Claim 7

That method defined in claim 1 characterized in that the step of placing the scale on said tubular members is performed by imprinting, and initiating said imprinting operation automatically upon determination of said predetermined reference point.

Claim 8

That method defined in claim 6 characterized in that said scale imprinting step is performed in time-delayed sequence and as the next tubular member is being positioned for scanning.

Claim 9

That method defined in claim 1 characterized in that said tubular members comprise sealed thermometers charged with a temperature sensitive fluid and includes the steps of orienting said thermometers in predetermined uniformly spaced relation, and indexing said thermometers individually to said scanning operation followed by dwell periods between said steps long enough to complete a scanning operation of maximum length.

Claim 10

That method defined in claim 8 characterized in the step of mounting said thermometers in parallelism on conveyor means formed with openings therethrough in general registry with the end portion of the column of thermally sensitive fluid.

Claim 11

Automatic apparatus for calibrating thermometers charged with a colored thermally sensitive fluid comprising, conveyor means provided with means for supporting a plurality of closely spaced thermometers arranged parallel to one another, means providing a scanning station equipped with scanning means movable lengthwise of a thermometer column in scanning position at said scanning station and including means operable to place a temperature scale on the thermometer with a predetermined graduation of the scale directly opposite the end of the column of thermally sensitive fluid in response to the location of the column end by said scanning means, and means for repeating the aforementioned operating cycle in rapid succession.

Claim 12

Automatic apparatus for calibrating thermometers charged with a colored thermally sensitive fluid comprising, conveyor means provided with means for supporting a plurality of closely spaced thermometers arranged parallel to one another, means providing a scanning station equipped with scanning means movable lengthwise of a thermometer column in scanning position at said scanning station and including means operable to place a temperature scale on the thermometer with a predetermined graduation of the scale directly opposite the end of the column of thermally sensitive fluid in response to the location of the column end by said scanning means, and means for repeating the aforementioned operating cycle in rapid succession.

Claim 13

Automatic apparatus as defined in claim 10 characterized in that said conveyor means has openings throughout opposite the position of the top of the fluid columns in the thermometers carried thereby past said scanning station.

Claim 14

Automatic apparatus as defined in claim 10 characterized in that said scanning station means includes ball bearing screw means for moving the same to-and-fro lengthwise of said thermometers, and reversible motor drive means for rotating said ball bearing screw means selectively in opposite directions to scan said thermometers to locate the top of said column of thermally sensitive fluid.

Claim 15

Automatic apparatus as defined in claim 10 characterized in that said scanning means comprises a main support, frame means supported for linear movement to-and-fro relative to said main support and including preloaded ball bearing screw and nut mechanism interconnecting said frame means and said main support, reversible motor means connected to ball bearing screw and nut mechanism to drive said frame means in either direction without lost motion, photoelectric scanning means mounted on said frame means for to-and-fro movement therewith, and control means for said photoelectric scanning means connected in circuit with reversible motor means and operable to control the operation of said motor means in response to a change in the object scanned as sensed by said photoelectric means.