Abstract A differential microcalorimeter having a pair of cylindrical thermopiles with a tubular test cell, axially carried within each thermopile. Each thermopile is fitted into an internally cylindrical, externally tapered, longitudinally segmented sleeve. The sleeve is fitted into a tapered well in a heat sink. Pressure against the sleeve to thrust it into the well reduces its diameter to more effectively grip the thermopile. The thermopile is a laminated arrangement of spacers and disk-shaped thermocouple members. Each spacer includes an inner ring gripping the core, an outer ring gripped by the wall of the sleeve and an intermediate insulator washer. Each thermocouple member consists of a disk-shaped insulator about which thermocouple wires are wrapped with the inner edge of the wires being supported upon the inner rings of the spacers and the outer edges supported upon the outer rings thereof. To effectively transmit heat from the core to the inner spacer rings through the wires to the outer spacer rings and to the heat sink, the inner spacer rings are slotted and tightly grip the core of the thermopile. The outer spacer rings are also slotted, and each outer spacer ring is thereby tightly gripped by the sleeve when the sleeve is reduced in diameter regardless of the possibility of variations in the outside diameter of the outer spacer rings. The spacer rings are anodized to insulate them from the thermocouple wires which rest against them.
In the microcalorimeter defined in claim 1, wherein: the inner rings are split so that each may bear against the core wall with a substantially uniform pressure.
Claim 2
Dependent Claim
56 words
In the microcalorimeter defined in claim 2, wherein the thermocouple members comprise: washers of insulating material having an inside diameter slightly greater than the inside diameter of the inner rings and an outside diameter slightly less than the outside diameter of the outer rings, whereby each washer is supported upon shoulders formed by the adjacent rings.
Claim 3
Dependent Claim
35 words
In the microcalorimeter defined in claim 3, wherein each thermocouple washer includes: wrappings of thermocouple wire about the washer, with one side presenting a metallic surface differing from the metallic surface of the other side.
Claim 4
Dependent Claim
40 words
In the microcalorimeter defined in claim 1, wherein: the reaction cell is extended substantially the length of the thermopile; and a charge means at the top of the cell adapted to drop materials into the cell for carrying out measurements.
Claim 5
Dependent Claim
28 words
In the microcalorimeter defined in claim 5, including: a stepped member within the reaction cell adapted to facilitate stirring the charge as it drops into the reaction cell.
Claim 6
Dependent Claim
29 words
In the microcalorimeter defined in claim 5, wherein: the charge means is a cylindrical, end-closed member having an open end which fits over the opening of the reaction cell.
Claim 7
Dependent Claim
54 words
In the microcalorimeter defined in claim 7, including: a diaphragm within the charge-means cup adapted to retain a charge of material at the top portion of the cup when it is fitted upon the reaction cell; and means to disrupt the diaphragm to permit the same to drop the charge into the reaction cell.