GB236980A - Improvements in calorimeters - Google Patents

Abstract

236,980. Scholes, G. E. March 19, 1924. Calorimeters.-In a bomb calorimeter, the closure joint between the shell and the cap is made by means of a ring of rubber &c. interposed between a seating on the shell and a seating on the cap, the joint being effected by the pressure produced within the bomb when gas is admitted and when combustion takes place. In the form shown in Figs. 1, 7 and 12, the shell A is of inverted form and is formed near its lower end with a shoulder a<1>, below which it is externally threaded to receive the cap B. Beyond the threaded part the external diameter of the shell is reduced to form a spigot a<3> extending nearly into contact with the cap. The closure ring C seats between the shoulder a<4> on the shell and a recess b<4> on the cap, the seating surfaces being preferably serrated. The ring C is preferably U- shaped in section, its upper and lower faces being slightly inclined to each other. Before making the joint the interior of the cap is charged with a small quantity of water which seals the end of the spigot and is forced by the pressure within the bomb into the recess containing the ring C. The crucible D is mounted in a ring d' carrying a split sleeve d<2> which can slide on a rod E extending through and insulated from the cap B. The ends of the strip F of fusible material pass through slots in the upper ends of rods E, E<1> and are gripped by sleeves c<2> having bevelled lower edges; the rod E<1> is carried by the cap B. The oxygen for combustion is admitted to the upper end of the shell through a connection G having a bore g' communicating by an oblique bore, a<6> with the shell. Within the member G is a non- return valve g<2> controlled by a spring g<4> and mounted on a stem q<3> at the lower end of which is a freely-mounted bell-shaped member g<7> engaging against a shoulder g<6>. The seating h' for the valve is carried by a union H screwing into the connection G to impart initial compression to the spring g'. A separate valve K is preferably provided for the withdrawal of the products of combustion. The rod E is provided with a plunger e<7> adapted to make electric contact with the water-calorimeter in which the bomb is placed, and the cap is provided with insulated legs I, the water-calorimeter and the fitting H being provided with connections for supplying the current for fusing the strip F. The invention is also applicable to the usual type of calorimeter having the cap B' at the top, Fig. 16, the shell A<1> being formed with a socket a<10> having a recess a<12>. In this form the cap and the shell are provided with spigots b13, a<13> enclosing the recess Q containing the ring C<1>. A tube q<1> conveys water from the base of the shell to the recess Q.