Patent Document

TECHNICAL FIELD 
     The present invention relates to rotating machinery such as gas or steam turbines and, specifically, to a quill or mounting block configuration for supporting an axial proximity probe used to measure axial movement of the machine rotor. 
     BACKGROUND OF THE INVENTION 
     Quills used for the axial proximity probes direct the probes parallel to the machine axis, and position the probe normal to the surface being measured. This current quill configuration does not allow easy assembly of the proximity probe hardware. The result is expensive proximity probes are sometimes destroyed during their installation. Of even more concern is the fact that, if the probe cannot be detected at fault during the installation process, then the problem reveals itself as an oil leak through the probe during the unit&#39;s operation. The unit then has to be shut down and the probe repaired. This is an expensive and time consuming process. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention relates to a new quill configuration which supports the proximity probe at an angle of 10° from the horizontal axis of the machine unit. The new quill allows accurate measurements of the rotor&#39;s axial movement with the advantage of easier installation without any compromise in the accuracy of the probe measurement. 
     Accordingly, in its broader aspects, the invention relates to a quill component for supporting a probe used to measure axial movement or a horizontally arranged rotor in a rotary machine, the quill comprising a block adapted to be mounted on a bearing component of the rotary machine, the block having a probe bore extending through the block at an angle of about 10° relative to the horizontally arranged rotor. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an end view of a quill in accordance with the invention; 
     FIG. 2 is a side section taken along the line  2 — 2  of FIG. 1; 
     FIG. 2A is a partial side section similar to FIG. 2 but illustrating a variation in the interior shape of the quill; 
     FIG. 3 is an opposite end view of the quill; and 
     FIG. 4 is a schematic partial view of a turbine and associated bearing end cap to which the quill is secured. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     With reference to FIGS. 1-3, the quill (or mounting block)  10  includes a generally vertically (or radially) oriented body portion  12  and an axially extending mounting flange portion  14 . Extending substantially transversely through the body portion  12  is a probe bore  16 , having a relatively larger diameter portion  18  and a relatively smaller diameter portion  20  interconnected by a tapered shoulder  22 . In the exemplary embodiment, portion  18  has a diameter of about 0.75 in. and portion  20  has a diameter of about 0.375 in. The forward or smaller diameter portion  20  is interiorly threaded at  24  and is adapted to receive an exteriorly threaded forward portion of a proximity probe P (shown only in phantom). The bore  16  extends through the body portion at an acute angle relative thereto, and at an angle of preferably about 10°, relative to horizontal (as viewed in FIG.  1 ), and relative to the rotor axis (FIG.  4 ). 
     The mounting flange portion  14  of the quill includes a first bore  26  adapted to receive a dowel pin which extends into a corresponding locator hole  28  on the interior surface  30  of the bearing cap, partially shown at  32 . A second mounting hole  34 , laterally offset relative to locator hole  26 , is used to secure the quill to the inside surface of the bearing cap by means of a suitable fastener such as a bolt or screw, to be threaded into hole  36 . A third bore  38  is also utilized to secure the quill to the bearing cap by means of a screw or bolt to be threaded into hole  40 . In order to have access to the bore  38 , a larger diameter counterbore  42  is provided within the quill extending from below the probe bore all the way to the mounting flange portion  14 . Prior to installation of the probe, it will be appreciated that with a suitable tool, access may be gained for purposes of installing or removing a bolt within the hole  38  during assembly or disassembly of the quill from the bearing end cap  32 . 
     In FIG. 2A, the inner taper  22  is extended from the relatively smaller diameter portion  20  to the bore  42 , effectively eliminating the constant diameter bore portion  18 . This tapered region (with a taper of about 20° relative to the bore axis), indicated by numeral  19 , facilitates the insertion of the probe P. 
     FIG. 4 illustrates the quill  10  secured to the interior surface  30  of the bearing end cap  32 , with probe P in place, with a leading end thereof in close proximity to the rotor, partially shown at  44 , with the rotor axis indicated at  46 . 
     The proximity probe itself forms no part of this invention, and may be any commercially available proximity probe. Suitable probes are commercially available from Bentley-Nevada Inc. The probe end is threaded into the forward section  20  of the bore  16  and located precisely relative to an adjacent rotor surface to thereby enable measurement of any axial movement of the rotor. Very fine threads are preferred to facilitate precise adjustment of the probe position. This new quill design is cheaper to manufacture, eases the installation of the probe and maintains the accuracy of the measurement of the rotor&#39;s axial movement. 
     While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Technology Category: 3