AU653436B2

AU653436B2 - Railway switch blade carrier

Info

Publication number: AU653436B2
Application number: AU26308/92A
Authority: AU
Inventors: Harold William George Lowe; Eric Sydney Murdoch Mcleod
Original assignee: TRAKTEC Pty Ltd
Current assignee: Individual
Priority date: 1991-10-09
Filing date: 1992-10-09
Publication date: 1994-09-29
Anticipated expiration: 2012-10-09
Also published as: AU2630892A

Description

65S.3q36

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT (Original) APPLICATION NUMBER:

LODGED:

COMPLETE SPECIFICATION LODGED:

ACCEPTED:

PUBLISHED:

RELATED ART: 0 0 *0 0* NAME OF APPLICANT: ADDRESS OF APPLICANT: ACTUAL INVENTOR(S): ADDRESS FOR SERVICE: TRAKTEC PTY LTD 008 709 840) 14 Munsey Street, Applecross, Western Australia, 6153, Australia HAROLD WILLIAM GEORGE LOWE and ERIC SYDNEY MURDOCH McLEOD KELVIN LORD AND COMPANY 4 Douro Place West Perth Western Australia 6005

AUSTRALIA

*6*fr tP r *0900* 0 rf COMPLETE SPECIFICATION FOR THE INVENTION ENTITLED: "RAILWAY SWITCH BLADE CARRIER" The following statement is a full description of this invention including the best method of performing it known to ;e/us:- 1 1 2 TITLE 3 "RAILWAY SWITCH BiADE CARRIER" 4 DESCRIPTION The present invention relates to a railway switch blade 6 carrier.

7 FIELD OF THE INVENTION 8 It is commonplace in railway switches to provide a steel 9 slide plate attached to a sleeper and to use this slide 10 plate as a support for a switch blade throughout the entire 11 region of transverse movement of the switch blade. The 12 force required to effect the switching operation is a 13 function of the frictional force opposing motion of the 14 switch blade over the steel slide plate. This frictional 15 force can be reduced by applying lubricant between the 16 opposing surfaces.

17 In practice dirt and other abrasive debris is collected by 18 the lubricant and a grinding medium is produced. This 19 induces wear and increases friction and there is a 20 resultant increase .in.the force required to operate the 21 switch.

22 SUMMARY OF THE INVENTION 23 The present invention provides a railway switch blade 24 carrier in which the sliding contact between the railway switch blade and the slide plate is replaced by a rolling 26 contact during movement of the switch blade.

27 In accordance with one aspect of the present invention 28 there is provided a railway switch blade carrier 29 characterised by a carrier member arranged to be mounted to TRAK1 1 2 3 4 6 7 8 9 10 11 12 13 14 15 17 16 17 18 19 20 21 22 23 24 26 27 28 29 31 2 a switch blade, a resilient deformable roller rotatably mounted to the carrier member and means for adjusting the position of the carrier member away from the switch blade so that, when the switch blade is unloaded, the switch blade is raised off the adjacent ground surface whilst the roller rests on the adjacent ground surface, but when the switch blade is subjected to a heavy load the roller is temporarily deformed, the switch blade temporarily contacts the adjacent ground surface and the load is transmitted to ground directly through the switch blade.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will now be described, by way of example, with reference to the accompanying drawings, in which:- Figure 1 is an upper perspective view of part of a railway switch showing a switch blade fitted with two switch blade carriers in accordance with the present invention; Figure 2 is an upper perspective view of a switch blade carrier in accordance with the present invention mounted to a switch blade; Figure 3 is a front elevation of the switch blade carrier of Figure 2; Figure 4 is an end elevation of the switch blade carrier of Figure 2 in moveable and non-load bearing condition; Figure 5 is a view similar to Figure 4 showing the switch blade carrier in load bearing condition; Figure 6 is a sectional end elevation of the switch blade carrier of the present invention along the line 3-3 in Figure 3; TRAK2 1 3 2 Figure 7 is a plan view of the switch blade carrier of the 3 present invention as seen in Figure 2 with part of a switch 4 blade broken away; and, Figure 8 is a cross section through a roller forming part 6 of the switch blade carrier of Figures 2 to 7.

7 DESCRIPTION OF THE INVENTION 8 In Figure 1 of the accompanying drawings there is shown a 9 stock rail 10 mounted in conventional manner on a plurality 1 0 of spaced, parallel sleepers 12. As shown, a switch blade S11 14 converges towards the stock rail 10. Adjacent a leading 12 end 16 of the switch blade 14, two or more sleepers 12 are S. 13 provided with respective metal slide plates 18. The switch 14 blade 14 is transversely moveable in known manner between a 15 first position in which, as shown, the leading end 16 is 16 laterally spaced from the stock rail 10 and a second 17 position in which the leading end 16 is in contact with the i 18 stock rail 19 Two railway switch blade carriers 20 in accordance with the 20 present invention are mounted to the switch blade 14 21 adjacent the leading end 16 on a side thereof remote from 22 the stock rail 10 so as to rest on respective slide plates 23 18. Depending on the use envisaged for the switch there 24 may be provided a single switch blade carrier 20 for light railways or three or more switch blade carriers 20 for 26 heavy railways.

27 As shown in Figures 2 to 7 of the accompanying drawings, 28 each railway switch blade carrier 20 comprises a bracket 22 29 shaped to engage snugly the fishing surfaces of the switch blade 14. A stud 24 passes through an aperture in a web 26 31 TRAK3 1 4 2 of the switch blade 14 (as can best be seen in Figures 4 3 and 5) and threadedly engages with a threaded aperture of 4 the bracket 22. The stud 24 is retained in place by a nut 28 threadedly engaged therewith on the opposite side of the '6 switch blade 14 from the bracket 22. A washer 30 is 7 disposed between the nut 28 and the web 26.

8 A pin 32 passes through a laterally extending hole in the 9 bracket 22. A grub screw 33 (see Figure 6) is located in a 10 threaded aperture so as to bear against the pin 32 and 11 retain it against axial movement. Further, there is 12 provided a carrier member 34 which comprises two lateral a .0 13 forwardly extending flanges 36 which are disposed on 14 opposite sides of the bracket 22. The flanges 36 each 15 contain a respective hole. The holes in the bracket 22 and S 16 the flanges 36 are all alignable so that the pin 32 can be 17 passed through all of them. The carrier member 34 acting 18 essentially as a bell crank, is able, in use, to pivot 19 about the pin 32.

20 The carrier member 34 also comprises two lateral rearwardly 21 extending flanges 38 provided with respective aligned 22 apertures. A roller 40 is mounted between the flanges 38.

23 As can be seen in Figure 6, the roller 40 comprises a steel 24 cylindrical hollow hub 41 and a generally cylindrical steel rim 42. The hub 41 and the rim 42 are interconnected by a 26 web 44 of resilient material which is capable of being 27 deformed and subsequently returning to its original shape 28 repeatedly. The web 44 may, for example, be formed of an 29 elastomeric material.

Further, the hub 41 contains a longitudinally extending 31 TRAK4 1 5 2 bore 46. Self-lubricating bushes 48 may be inserted into 3 the bore 46 to reduce friction between the bush 46 and a 4 pin 50 to be described.

A pin 50 is inserted through an aperture in a flange 38, 6 the bore 46 and the other aperture in the other flange 38..

7 As shown, the pin 50 may be retained in place by a split 8 pin 52 and a locking pin 52a (to prevent rotation) engaged 9 with small apertures at the ends of the pin 50 in known 10 manner. The roller 40 is mounted on the pin 50 in such •6co 1 manner that the roller 40 can roll freely on the slide ;12 plate 18 when the blade carrier 34 is required to move the 13 switch blade 14 laterally.

14 Further, the carrier 34 is provided with an externally 15 threaded adjusting screw 54 which is threadedly engaged 16 with an aperture in a transverse web 57 in the carrier 34 17 (see Figures 6 and 7) and passes through the carrier 34 so 18 as to bear against the bracket 22. The adjusting screw 54 19 is threadedly engaged with a lock nut 55. Further, the 20 adjusting screw 54 is provided with opposed flats 56 at the 21 end thereof remote from the bracket 22. The flats 56 which 22 enable the screw 54 to be rotatably moved relative to the 23 carrier 34 and to pivot the carrier 34 about the pin 32 24 until the switch blade 14 is, in its unloaded condition, lifted clear of the slide plate 18 as shown in Figure 4.

26 When the switch blade is in the desired lifted position, 27 the lock nut 55 is tightened against the carrier 34 to 28 maintain the switch blade carrier 20 in the desired 29 position.

In operation, the configuration of the railway switch blade 31 TRAKS 1 6 2 carriers 20 and the switch blade 14 is such that the 3 rollers 40 rest on the slide plates 18 and serve to lift 4 the switch blade 14 clear of the slide plates 18 as can be seen in Figure 4. Thus, in the unloaded configuration of 6 the switch blade 14 it is supported on the slide plate 18 7 by the carrier 8 Further, if it is desired to move the switch blade 14 9 laterally to switch it from one position to another this is 10 effected by known means. The rollers 40 simply roll across 11 the slide plates 18. Theswitch blade 14 does not contact 12 the slide plates 18.

13 However, as can be seen in Figure 5, when the switch blade 14 14 is in a desired position and a train wheel 60 passes 15 over it, then the switch blade 14 is subject to a massive 16 downward pressure caused by the weight of the train. In 17 this condition the switch blade 14 is pressed downwardly 18 until it contacts the slide plates 18. Thus, the weight of 19 the switch blade 14 and the train is taken by the slide 20 plates 18 and the sleepers 12. The switch blade 14 is able 21 to move downwardly into contact with the slide plates 18 by 22 deformation of the resilient web 44 of the rollers 40 such 23 that the pins 50 adopt temporarily a low position within 24 the rims 42.

Thus, whilst huge vertical forces are transmitted between 26 the switch blade 14 and the sleeper 12 when a train load is 27 being carried, only the weight of the switch blade 14 is 28 supported by the roller 40 when the switch is not 29 occupied. Thus, during switch operation only the weight of the switch blade 14 has to be accommodated.

31 TRAK6 1 7 2 When a train load is being supported the vertical movement 3 of the switch blade 14 into contact with the slide plate 18 4 bypasses the rollers 40 so that the rollers 40 do not have to be designed to carry heavy loads. Once the train has 6 passed the load onthe rollers 40 is relieved and the 7 rollers 40 then resiliently return to its original 8 condition shown in Figure 4 and lift the switch blade 14 9 clear of the slide plates 18 again.

Thus, as is apparent from the above description, the switch 11 blade 14 is only moved transversely when it is not under 12 load and the weight of the switch blade 14 when so moved is 13 taken by the roller 14. When the switch blade 14 is under 14 heavy load it is not moved it is not required to move S' 15 laterally and the load is transmitted directly to ground 16 through the slide plate 18.

17 Modifications and variations such as would be apparent to a 18 skilled addressee are deemed within the scope of the 19 present invention.

o* 21 22 23 24 26 27 28 29 31 TRAK7