Patent GB-694935-A (GB)
Title: Improvements in apparatus for checking the gauge of railway tracks
IPC: E01B35/04
Filed: 1952-01-11
Abstract: 694,935. Linear-dimension gauges. BIENFAIT, L. A. J., and DUPUICH, G. L. Jan. 11, 1952 [Jan. 19, 1951; April 23, 1951], No. 919/52. Class 106 (ii). A travelling rail track gauge has means for continuously and simultaneously gauging the width of the track at two spaced apart points as well as the difference in track gauge between these points. In Fig. 1 a light car or lorry 1 rolling on rails 2 and 3 has a pair of wheels 5 and 7 at its forward end and a pair of wheels 4 and 6 at its rearward end, these wheels being horizontally disposed to engage the inner edges of the rails 2 and 3. As shown, the wheels 6 and 7 are movable against spring means 12 and 13 in accordance with the width of the track and this movement is transferred through wires'14 and 16 to pivoted pointers 24 and 25. The pointers 24 and 25 indicate on a scale 27 the width of the track between the wheels 4 and 6 and between the wheels 5 and 7 respectively. The scale reading between the pointers 24 and 25 is a measure of the change in track width between the front and rear wheels. Fig. 2 shows a modification in which the wheels 6 and 7 are carried by bent levers 8a-18 and 9a-19 pivoted on frame 1, the wheels 6 and 7 being urged by springs 12a and 13a into engagement with the rail 3. The portions 18 and 19 of these bent levers constitute pointers moving over two scales 20 and 21 respectively to indicate track gauge. The difference in value between the two track gauges is read on a system of lines 22 each of which indicates a given value of this difference and being marked by the point of intersection 23 of the pointers 18 and 19. Let the track gauge between the wheels 4 and 6 be el and between the wheels 5 and 7 be e2 and let it be that the value of (e2 - el) shall not exceed a predetermined value Œ<SP>t</SP>. Then, if it is found during gauging operations that the distance el is in need of correction by a value c1, it may be that the distance e2 is also in need of a correction c2 in order that the value of t shall not be exceeded. The apparatus and means illustrated in Figs. 4, 5 and 6 is for use in conjunction with the rail track gauge and enables any such valves of c2 required by the track to be easily ascertainable. Fig. 4 is a chart for use when t is one unit. The horizontal lines on the chart correspond to different values of (e2-e1) and the columns correspond to different values of c1. Thus, if the difference between the track gauges (e2 - e1), is +1 and it is found that the distance e1 should be increased by cl=+3, then the minimum adjustment necessary to e2 is c2=+1, if t is to remain within the limits Œ 1. Fig. 5 shows a sliding scale for use with the track gauge whereby a known value of (e2 - el) can be selected on a movable scale 30 and aligned with any known necessary correction cl on a fixed scale 29. When this has been done, any necessary correction c2 of the value e2 to maintain t within the limits Œ1 is visible through a hole 31 in the movable scale 30. A further device, Fig. 6, for determining any necessary value of c2 is arranged to co-operate with the pointers 24 and 25 in Fig. 1. On the pivot 26 of these pointers is mounted a sector 32 bearing a first scale of graduations c1 along its edge adjacent to the scale 27 and a second scale of graduations c2 along an arc as shown at 33. Pointer 24 has an aperture 31 through which the scale 33 is visible. As above described, the angular distance between the ends of the pointers 24 and 25 is automatically proportional to (e2 - el). Therefore, everything takes place as if the end of the pointer 25 indicated, on an imaginary scale rigid with pointer 24 and having its zero at the end of said pointer 24, the value of (e2 - el). Sector 32 is adjusted so that the graduations of scale c1 which corresponds to the values of c1 is made to coincide with the end of the pointer 25. Consequently, the value read on scale c2 through the hole 31 of the pointer 24 is the desired value of c2. The apparatus and means illustrated in Figs. 4, 5 and 6 may be modified to give values of c2 for values of t other than Œ1, e.g. Œ2 or Œ3 units. As previously stated, the scale reading (e2-e1) between the pointers 24 and 25, Figs. 1 and 6, is a measure of the change in track width between the front and rear wheels. This measure is also given by the intersection in Fig. 6 of the right-hand side of the pointer 25 with a scale 28 on the pointer 24.