Patent GB-240426-A (GB)
Title: Improvements in optical methods of and devices for testing the position of two axial directions
IPC: G01B11/27
Filed: 1925-08-28
Abstract: 240,426. Zeiss, C. [Firm of]. Sept. 23. 1924, [Convention date]. Testing - apparatus, auxiliary.-For testing the relative directions of two axes lying in the same plane a telescope is used in conjunction with a collimating device, a sighting mark in the eyepiece of the telescope being viewed simultaneously with the image of a sighting mark in the collimator. In some examples the axis of the telescope embraces the angle with one axial direction which corresponds to the angle between the two directions, and in other examples the path of the rays along one axial direction is deflected into the telescope which is parallel to the other axial direction by means of a reflector system, e.g. a reflector or prism, placed between the collimator system and the eye-piece of the telescope. The various forms of the apparatus are described with reference to the directions of the axes of various engine parts. The following three examples are typical of a large number described in the Specification. In the first example, Figs. 1 - - 5, a collimator, comprising a collective lens 2 and a ground glass screen 3 mounted in a casing 1, is provided with two sleeves 4 slipped on to the casing 1 and secured by screws 5. Three rods 6 in each sleeve are ground at their outer ends to fit the boring 7 the axial direction of which with respect to the face 16 it is desired to test. A telescope 9, having an objective 10 and a graticuled eyepiece 12, 13 is supported on a fork-shaped body 14 carrying an accurately worked strip 15, which bears against the surface 16. A graduated disc 18 attached to the support 14 enables the telescope to be set at the required angle, and examination of the relative position of the cross-lines 19 in the eyepiece of the telescope 9 with the image of the mark 8 on the ground glass screen of the collimator 'indicates the extent of the error of the two axial directions. The size of the. circle 8 is determined so that when the intersection of the cross-lines lies within the image of the circle the error of the angular direction is less than the maximum error allowable. To test the axial position of the bearing 23. Fig. 6 with respect to that of a cylinder 22, the telescope 24 is mounted in a bearing 32 supported on a frame 34 carrying a worked strip 35 pressed against the surface of the cylinder bv a screw 42. In this example the ground end 47 of a shaft 43 supported in the bearing 23 reflects light received from the light-tube 25 by way of the reflector 30 and objective 26, and a reflected image of the cross-lines 31 is viewed simultaneously with the actual cross-lines bv the eyepiece 29. The bearing 32 of the telescope is situated at the required angle to the face 35 of the support. In a further example. Fig. 23, a mark carrier 75 is mounted in a bearing 128 and a telescope body 127 is mounted in a bearing 129, the axes of which bearings are to be parallel. The telescope 127 is fitted with an eyepiece 131 carrying a mark 134, and also with an objective 130 and a reflector system 135 - - 138, consisting of plane and roof prisms, the prisms 137, 138 being mounted in a casing 140. which is rotatably connected to the casing 139. The reflector system bv this means is adjustable so that the image of the mark 76 in the bearing 128 is seen in the eyepiece 131, as shown in Fig. 24. Other examples deal with testing the directions of the axes of two shafts, a shaft and bearing and by a sliding reflector system the correctnes of the axial distance of two parallel shafts and/or bearings.