Baseline control for a differential scanning calorimeter

• US 4,530,608 A
• Filed: 05/14/1984
• Issued: 07/23/1985
• Est. Priority Date: 05/14/1984
• Status: Expired due to Term

• Current Assignee: Perkin-Elmer Corporation The Main AVE Morwalk CT
• Original Assignee: Perkinelmer Incorporated
• Inventors: O'Neill, Michael J.
• Primary Examiner(s): Stephan, Steven L.
• Assistant Examiner(s): Will, Thomas B.
• Application Number:
  US06/609,630
• Time in Patent Office: 435 Days
• Field of Search: 374/10, 374/11, 374/12, 374/13, 110/190, 110/191, 110/185, 236/78 A, 219/483, 219/486, 219/497, 219/501
• US Class Current: 374/11
• CPC Class Codes: G01K 17/00 Measuring quantity of heat measuring temperature by calorimetry G01K3/00 - G01K11/00; specially adapted for measuring thermal properties of materials, e.g. specific heat, heat of combustion G01N

Abstract

A differential scanning calorimeter includes a baseline correction apparatus which simultaneously corrects for both linear and curvilinear heat flow variation between the sample and reference holders.

Claims

1. A differential scanning calorimeter correction control apparatus;

said apparatus comprising;

a sample holder and a reference holder, each said holder having a heater element and a sensor element associated therewith; and

means for simultaneously compensating for both linear and curvilinear heat flow variations between said sample holder and said reference holder.

2. Apparatus as claimed in claim 1 wherein said means includes:

a voltage multiplier network for producing a signal for compensating for said linear heat flow variations;

a bridge balancing network for producing a signal for compensating for said curvilinear heat flow variations; and

means for simultaneously varying at least one element of each of said networks whereby said compensating signals are simultaneously controlled.

3. Apparatus as claimed in claim 2 further comprising:

means for summing said compensating signals whereby a single correction signal is produced which single correction signal is representative of the power compensation required to compensate for said linear and curvilinear heat loss variations.

4. Apparatus as claimed in claim 2 wherein;

said voltage multiplier network includes a single variable resistor; and

said bridge balancing network including a single variable resistor.

5. Apparatus as claimed in claim 4 wherein said means for simultaneously varying said variable resistors is a single control member.