GB233410A - Improvements in revolving nose-pieces for microscopes and the like - Google Patents

Abstract

233,410. Sloan, R. A. Feb. 6, 1924. Microscopes.-Revolving nosepieces for microscopes are provided with means for independently adjusting the positions of the objectives in two directions to ensure that when the objectives are turned into the optical axis of the microscope their axes coincide therewith. The adjustments are applied, in one example, to the objectives individually, and in a second example to the rotor carrying the objectives. The stator S of the nosepiece is secured to the nose 2 of the microscope tube 3, preferably by the conicallyheaded screwed ferrule 5 described in Specification 120,127. For each objective is provided a thin collar 6 into which it is screwed. Each collar 6 has a flat base or flange 7 normal to the axis, which is adjustably clamped against a flat facet 8 on the rotor R. The means for clamping comprises three conically-headed screws 9 engaging on one side bevelled portions 11, 12 of the flange 7, and on the other side semi-cylindrical recesses 10 formed in the rotor. By adjusting the screws 9 the objectives are accurately and individually located in the rotor so that their optical axes will coincide with that of the microscope when turned into their operative position. The screws 9 may be equally spaced round the collar 6. In the modification in which the position of the rotor determines the adjustment of the objectives, the pivotal attachment of the rotor R to the stator S provides for the requisite radial freedom; the central hole 27 being somewhat larger than the central stud 28. The adjusting means consist of a pair of hardened steel screws P, F, for each objective screwed radially into the edge of the rotor R. One of the screws P has a conical end and the other screw F a flat end, the former being arranged nearly diametrically opposite the corresponding objective and the latter about a quadrant from the former. Each screw is locked by a set-screw 37. The ends of the screws P, F contact with the edge of a steel ring 31 secured to the stator. A wire spring 34 carried by the stator S exerts a radial inward pressure on the three pins 35 attached to the rotor R. The force exerted by the spring 34 may be resolved into two components acting along the axes of the adjusting screws P, F, by which the corresponding objective is.accurately positioned. To change the objective, the rotor R is first pressed against the action of the spring to release the point of the screw P and then turned until the next screw P snaps into position. To retain the rotor R in position a rigid detent 18 is fitted pivoting on the screw 24 about two pins 19 in the stator S and engaging a pin 22 in the rotor R bv means of a slot 21. The rotor R is released by pressing the lever 25 of the detent 18 against the action of the spring 23 on the screw 24.